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Additive Manufacturing - Science topic

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Questions related to Additive Manufacturing
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Hello everyone,
there seems to be a lack of resources, even though SLA additive manufacturing is widely used. Would anyone be so kind as to point me towards a source determining the Poisson's ratio of standard photopolymers in cured state? I'd be especially interested in Formlabs Clear resin and Formlabs Tough 2000. Their documentation does not provide a number, unfortunately, and literature results for other resins are surprisingly scarce as well.
Thank you all in advance.
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Good day! As for the information, that I found, Poisson's ratio of Formlabs Clear resin is 0.35. Please find the following links as useful:
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Have the problems of cracking, porosity, and uneven distribution of microstructure in additive manufacturing cemented carbide (WC-12Co) been solved? Are there any products in the industry right now?
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I noticed that recent articles mentioned coating Co or Ni on WC powder surface to improve the fluidity of powder. However, there are many ways to coat the material on the powder surface, it is not clear which is best. Hope you have other ways.
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Hello,
I am doing an additive manufacturing simulation in ABAQUS/CAE 2017.
I have two working subroutines: DFLUX and UEPACTIVATIONVOL which both do their jobs correctly in separate models. I need to combine them but for my moving surface flux, the surface I define in the model does not work due to the activating elements during the analysis form the UEPACTIVATIONVOL. (The surface I define in the GUI for the heat flux does not exist at t = 0 since the elements are inactive)
Is there a way to define the top element face as a surface and change that in a subroutine for my DFLUX subroutine to call so the heat source will be applied on the surface of elements on one layer and then apply to the elements top face on the next layer?
Thanks in advance for your help!
Shaun
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Manik Patil You as well. Best of luck!
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Does Big Area Additive Manufacturing (BAAM) demonstrate any plastic deformation before crack initiation?
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There's a thesis that may answer your question here:
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Hello,
I am trying to simulate a laser path to understand various mechanical effects because of using a DED to build a cube of 15mm*15mm*15mm in ANSYS workbench using DED Process extension(attached) for Tungsten.
The extension enables Transient thermal followed by static structural, although I am not sure how to set up the process. I could not find any leads on the ansys on the setup unlike for the moving heat source (many sources available)... I was wondering if anyone can share how to enable the process.
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I am also trying to incorporate the laser in the ansys..but it's very difficult to find any source
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XPS analysis was performed for O 1s , and the following results were obtained.
I can see C=O, C-O, Al2O3 bond.
but, I don't know why C=O / C-O bonds are exist, what C=O / C-O bonds means.
Please interpret this result.
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Sc Park There always appears to be a large amount of C on a surface - could be from absorbed CO2 in the atmosphere in your case leading to carbonate formation on the surface. Other theories are that organic matter in the atmosphere also contribute to (or are the majority of) the C found on surfaces. I would Ar+ etch 15 atomic layers or so to see what you then obtain.
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Hello everyone,
I am trying to model the process stage (Gate to Gate) of FDM on SimaPro. I understand that I need to decide upon my inputs and outputs as well as system boundary before doing that. I am trying to do this properly and was wondering if anyone can advise more on this methodology (i.e., how to decide upon the values for the raw material input and electricity?, etc...).
Any response is very much appreciated. Thank you.
Useful Article: Methodology for systematic analysis and improvement of manufacturing unit process life-cycle inventory (UPLCI) —CO2PE! initiative (cooperative effort on process emissions in manufacturing). Part 1: Methodology description.
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For FDM SimaPro modelling in gate-to-gate first you should have clear system boundaries based on the research scope. I would like to suggest the following research articles for in-depth study:
Hope them helps you
Best regards,
Shuraik
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AlSi10Mg powder was made by gas-atomizing.
and this powder has poor flowability.
so, I tried to dry the AlSi10Mg powder on vacuum, but it doesn't work.
How can I improve flowability AlSi10Mg powder for Additive Manufacturing?
and, Why AlSi10Mg powder's flowability is so poor?
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Your powder contains particles of different sizes. One speaks here of a wide particle size distribution. This is bad for flowability, since the finest particles tend to form lumps. In order to improve the flowability of the powder you have to remove the finest particles from the powder. There are basically two ways of doing this: wet sieving (vibration sieving machine) with a 20-30 micrometer sieve or compressed air screening using a cyclone screener.
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I created 50 interactions(welding-1 to welding-50) such that half of the region was reactivated through these interaction,which was previously deactivated , through the following code:
Tol=.00000000001
Speed=0.01
for i in range (1,51):
mdb.models['Model-2'].ModelChange(activeInStep=True,createStepName='welding_'+str(i),includeStrain=False,name='welding_'+str(i),region=Region(
elements=mdb.models['Model-2'].rootAssembly.instances['Part-1-1'].elements.getByBoundingBox(-Tol+Speed*(i-1),-Tol,-Tol,Tol+Speed*i,.0025+Tol,Tol+0.002)),
regionType=ELEMENTS)
But when I tried to view region reactivated in any of these newly created interaction,following error showed up,"At least part of the region of the selected interaction has been suppressed,deleted or excuded or is a part of reference representation".I am unable to understand the error.The deactivated region is a cuboid with X coordinate ranging from (0,0.5) ,Y coordinate ranging from (0,0.0025),Z coordinate value from (0,0.004).The direction of welding is positive X axis.Through these interactions I am trying to reactivate lower half of this cuboid with Z axis of the reactivated region ranging from (0,0.002) and range of X and Y coordinate being the same as that of the deactivated region.I have attached an image of abaqus model.
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Hi Atul,
I have the same problem in my modeling. could you finally resolve this error or not? I would appreciate it if you can share with me what you have done.
Regards,
Hossein
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Textbooks about the managerial aspects of Digital Transformation and Industry 4.0 for academic teaching with exercises and case studies.
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Perhaps look to good articles … for a book it is not yet the time
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I am working on ceramic resins. I First mixed the ceramic with surfactant and a solvent. Ballmilled for 1 hours. To facilitate chemisoprtion i kept the solution in oven for 130 degree for 180 minutes. I found the white ceramic powder the turned brown in colour. I would like to know the reason for the outcome.
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neutral
based on the composition of material surface
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I am planning to measuring residual stress using Nanoindentation.
And I need the stress-free sample for reference.
The sample that I want to measure is AlSi10Mg , makes Additive Manufacturing.
so, how to make stree-free sample?
heat treatment? , how can i decide to proper heat treatment temperature?
Electric Discharge Machining?
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It is quite hard to produce a truly stress-free sample. Stress relief annealing of AlSi10Mg is tricky as you might change the hardness of your samples, see Mertens, et al 2015 - THERMAL TREATMENTS OF AlSi10Mg PROCESSED BY LASER BEAM MELTING (Hardness was reduced by ~ 10 % due to the 250°C/2h heat treatment)
Non precipitation hardenable alloys are typically annealed at 200°C till 300°C and then slowly cooled e.g. in the furnace (GDA Merkblatt W7). Whereby, a higher temperature should be able to achieve a lover stress level. If your samples have the capability of a precipitation hardening and your residual stress is related to a fast cooling steep, "up-hill quenching" (e.g. -196°C and then heating up in a steam bath) might be suitable. (see ASM Handbook vol. 4 Heat Treatment)
The proper temperature depends on the condition (amount of Mg and Si in solution or/and the precipitations) of your samples.
Every machining (even EDM) is able to introduce residual stresses close to the surface. Therefore, you might be better of with a chemical enchant or rather electrolytic polishing before the testing and after your stress relief treatment.
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Dear Researchers, Need to fabricate specimen from CNT powder using additive manufacturing technique and What could be suitable process for fabrication. Any vendors available for specimen preparation.
Thanks in advance
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Metal AM/3D Printing processes have seen massive R&D efforts over the last few years, which have helped improve the indsutrialisation efforts of AM processes. I would be very interested to hear everyone's thoughts on what the topics are, that need to be investigated and developed over the next 5 years by those in research.
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Actually, Powder Bed Fusion (PBF) is an advanced AM technology that has matured over an extended period of research and industrial development. This technology development has enabled wide uptake of commercial applications of PBF technology, particularly for the production of high-value products that are not technically feasible with traditionally manufacturing processes.
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Hi all, i would like to know what are some of the key considerations one has when it comes to purchasing metal powders for printing? Price point is definitely a consideration, how about quality? or even availability of powder sizes or availability of small batch like (10kg?) is that a challenge in purchase of powders? any other challenges when you face when it comes to purchasing metal powders?
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Actually, Metal powders used in AM processes are typically microscopic in size (< 100 µm) and often pose toxicity, reactivity, combustibility and instability hazards. Dust clouds, formed for example by the accidental swirling of powders, have the potential to catch fire and explode under certain conditions.
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What are advantages of smart factories?
I've recently published the following article in the Korea Times.
And how do you feel about smart factories? Please be as specific as possible when expressing your comments.
What are advantages of smart factories?
Humanity has come a long way from its earliest traces of civilization. Through industrialization, advancement has been brought to the world like never before. The introduction of human labor and later on machines were heightened to a great emphasis, being the main fuel of the economy. Manufacturing became a core concept in terms of civilization during the height of capitalism; a necessity in providing for the needs of citizens in terms of products, services and jobs among others. It is probably right to say that humanity's current habits revolve around the whims and ways of capitalism. Despite the fact that humanity has highly benefited from different stages of industrialization, it has also revealed how it can be perilous and detrimental to citizens throughout the years in different aspects. One of the dangers that capitalism and intensive labor pose toward workers would be the tendency of burnout from excessive and inhumane workloads. Burnout can also come from repetitive tasks, whereas humans are naturally inclined to look for new things to explore and experience from time to time. More so, labor workers also frequently encounter the risks of unjust labor treatment, particularly in relation to wages, benefits and regulations. Amid the introduction of artificial intelligence (AI) technology during the current Industrial Revolution (IR), the same issues regarding the negative sides of labor and capitalism maintain their prevalence. This is where the idea of smart factories enters. In the simplest sense, a smart factory is a manufacturing site wherein the traditional workload is combined with smart machinery powered by huge data and technological systems. Smart factories are factories that are highly improved, innovated, and advanced, branching out as a contribution of IR 4.0. One of the great benefits that smart factories introduce would be the ability to shorten the duration and costs of operations in manufacturing. This is because it is highly flexible in adapting with the usual processes that happen in the factory through the means of storage and analysis of huge data. In doing so, the manufacturing processes became more efficient and effective, lessening the workload that employees are usually tasked with. A smart factory provides for the reduction of manufacturing process times and costs by adapting and optimizing operations as well as storing and analyzing vast amounts of data in real time. This leads to a more flexible, efficient, and autonomous production by encouraging workers to focus on improving processes rather than on mundane jobs, resulting in high value. Smart factories gradually gear up society for IR 5.0, with the goal of creating a people-centered economy rather than a task-centric economy. As smart factories aim to lessen the workloads of human workers, it allows them to have more time for other fundamental things that comprise their lives, other than their jobs and careers. Smart factories give hope for individuals to have more time for recreation and leisure, as well as time spent with family, friends, and meeting new individuals instead of working for eight hours straight. A smart factory strategy does not equate to a total replacement and retrenchment of employees with machines. Rather, it would employ the fusion of the work and effort of both humans and smart technology-powered machines. It adapts a system that is highly-digitalized wherein real-time data is optimized. Smart machines or smart robots can be programmed with repetitive and routine tasks that are usually compiled by the human workforce. Simply put, it brings forth a workplace and lifestyle for individuals that is both sustainable and humane. It is well known that the height of capitalism involves intense competition within and outside of firms and companies. With that being said, the utilization of smart factories and artificial intelligence allows the opportunity for robots to be those involved in the competitions instead of relying on humans. This can be done in the way that smart robots will be mainly responsible for the heavy processes done during production. Thus, they will be liable for the quality of the manufactured goods which are the foundation of a company's competency compared to other companies. In turn, this would relieve the human workforce from the added pressure that is embedded in the production process for the obvious reasons that they are held responsible for the product quality and output. Through smart robots, quality products and their output can be made, which will be the basis for the reputation of the company's name. External influences such as the macroeconomy and the pressure it places on a firm and its employees can play a significant role in fostering a toxic workplace. Smart factories give us a chance to save humanity and society by providing a realistic, attainable and considerate alternative for the people. Such an approach would provide the steps for a healthier and more sustainable lifestyle for humans in terms of realigning their relationship with work. Lastly, it promotes a society that looks out for the well-being of its citizens, instead of looking at them as mere workers. Rushan Ziatdinov (ziatdinov.rushan@gmail.com) is a professor in the Department of Industrial Engineering at Keimyung University, Daegu.
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Smart factories optimize efficiency and productivity by extending the capabilities of both manufacturing devices and people. By focusing on creating an agile, iterative production process through data collection, smart factories can aid decision-making processes with stronger evidence. https://tulip.co/glossary/what-is-a-smart-factory-and-what-it-means-for-you/
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We have done some of our own work with early DIY 3D printers that for new users showed failure rates as high as 20%. I know from our own experience it is much lower now - but have you seen or published average failure rates of plastic 3D printers - either in industry or from your own labs?
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I've been doing 3D FDM (PLA) printing since 2012. In this particular case, main flailure ou flaws are misalignment of mechanical assembly, from housing to gears and bolted parts. Besides, of course, wear of the extruder nozzle and its cleaning, which we must remember is not eternal. I recommend changing the nozzle every 50-60 hours of printing, having gone through many cleanings.
One thing that cannot be overlooked are gear head fixing screws on stepper motors, these are called cotter pins, they are headless screws inserted into gear body. Due to the "jumps" of printing pieces with right angles (Dirac delta effect - unit step impulse). These tiny screws loosen over time and can often "disappear" given their tiny size. I always recommend retightening along with the rest of structure.
As for 3D printing failure, I think main reason is quality and color of PLA plastic used. I've noticed during these 10 years that I have fewer problems with transparent (natural), white and light gray plastics. Colors with a lot of pigmentation more often clog the extruder nozzle. I also prefer to use unheated tables.
I realized over time that 3D printer needs to stay in a power-on with no air circulation. Mild air displacement temperature changes during a long print (30-60h) change quality of finish.
Another important factor is alignment adjustment of assembly and extruder with table. It must be calibrated every 20 hours of printing, including a raft on first layer to check if the alignment is still good!
I think these are the tips, and it really is sad and annoying when a crash ou failure occurs, but keeping in mind what I said earlier, it's easier to avoid failures!
Good luck!
My best regards,
Filipe
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If yes, please contact me.
We are looking for partners in joint research.
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Our system can process either wires up to 2.2 mm diameter or rods up to 10 mm diameter. Just need to select machine configuration during order registration.
Other methods of raw material supply in our area of interest for joint research are e.g. induction melting of larger rods or pellets incl. alloying or AM scrap reuse (so called re-powder).
As in my initial question: We are looking for partners in joint research in different areas – feedstock input and melting, material characterization after alloying, powder applications (e.g. cermetal / MMC, inter-metallics), scale-up and full automatization for industrial scale production, system integration with printers and others research topics.
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Dear Colleagues,
If you are researcher who is studying or already published on Industry 4.0 or digital transformation topic, what is your hottest issue in this field?
Your answers will guide us in linking the perceptions of experts with bibliometric analysis results.
Thanks in advance for your contribution.
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Hello dear colleagues,
I want to reproduce the surface topography of metal additive manufacturing samples in CAD and CAE environments. What is the best way to capture surface topography and how can I reproduce it?
Any recommendation is appreciated in advance.
Best regards,
Hamidreza
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Hi, If you want to capture all the surface features (pores, cavities) generated during the LPBF process, especially Rv surface roughness with high resolution, use a laser scanning confocal microscope.
See our paper:
"Enhancement of electrical conductivity and corrosion resistance by silver shell‑copper core coating of additively manufactured AlSi10Mg alloy"
  • Surface and Coatings Technology 403(C):126426
  • DOI:10.1016/j.surfcoat.2020.126426
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I am interested in removing defects during metal LPBF like orientation adjustment, residual stresses, cracks, part failure, etc.
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For predictive simulation of these processes, we use Autodesk Netabb (https://www.autodesk.de/products/netfabb/features), which works great but is cost-intensive. We also use the Simulia Abaqus "AM Modeler" Plugin (https://info.simuleon.com/blog/using-abaqus-to-simulate-additive-manufacturing-printing-an-optimized-hip-implant) which costs less and also delivers good results for this process. These simulations might potentially help you to reduce the thermal and stress-induced defects and deformations in your parts. Further, it might support you to improve your support structure placement (if required for your process).
When considering micro-defects and the quality of the material after manufacturing, you should specify the type of defects that should be "removed". Maybe a simulation would not be appropriate and you should consider an In-Line process monitoring and control for your process, combined with a proper "Design of Experiments". The data achieved by this procedure could be used to improve the simulations mentioned above by considering your materials and machines constraints.
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As we all know the best particle size for SLM is around 40um.
I was looking for a lab scale machine to produce my needed metal powders and I found ATO Lab Atomizer machine, although the company claims that the output powder of the machine is suitable for SLM but in its catalogue it is mentioned that the particle sizes are between 20 and 120um.
I am curious to know can I use that powder for SLM AD?
and also how many percent of that powder is under 50um?!
they did not share any size distribution graph!
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Dear Mrs. Cheng,
As for ultrasonic atomization by itself, ultrasonic frequency is the most important factor. You could take o look at our new paper on technology.
You could also take a look at the PSD we have obtained at the rePowder device by AMAZEMET for two different frequencies. As the inventor of both the abovementioned devices, I would suggest taking an in-depth look at the material feedstock used by both setups.
Best regards,
Łukasz Żrodowski
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Hello!
I'm starting a Thesis on the topic of Additive Manufacturing with the combination of flexible manufacturing/process build control. Can anyone suggest any research topic I can work on? Any reference paper or Thesis would be appreciated. Also, can you suggest which software I'll have to use in this research topic? Ansys?
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Hi Daniyal,
are you starting a master' thesis ? Will it then be for 6 months ? Some topics you could work on. Will it be on Metal AM ?
1. Guidelines for enabling in process monitoring and control of AM ( Metal or Polymer) processes.
2. Studying and comparing different post process treatments for enabling flexible/hybrid manufacturing with AM.
3. Studying and developing different digital error detection and quality control methodologies for AM.
There has been research done in all these fields, you can find some for example like
Good luck with your thesis!
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My intention is to be able to see by LOM, the melt pools produced by the additive manufacturing process, and also the grain formation.
Any help or advice would be appreciated!
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Hello,
I am working on a project "Structural simulation of 3D printed part - PLA material - FDM method" and for that I am doing simulation in ABAQUS AM modeler but I got stuck in the middle.
I got the error "EVENT SERIES data error". I do not know how to generate event series from .gcode file. Please someone land me any example file or the way to generate a event series file fr that?
Thank you!
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In AM model tab, you can find data setup, model setup, and simulation setup. Different data structure include parameter table, property table, and event series.
If you want define data in time and space dependent, you need event series. It is a combination of amplitude curve and path. Within event series, you must define field variables. The structure consists of
Time-1, x1, y1, z1
Filed value-1 (..., ...)
Time-2, x2, y2, z2
Filed value-2 (..., ...)
There are predefined event series also.
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Texture data from XRD is available along with the ODF
Finding difficulty in interpretation of Contour maps and ODF
Interpretation of the Contour maps including the type of Texture, Calculating the Texture index and orientation distribution function.
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If you can share more specific info about your problem then probably it can be sorted out. message me if you are comfortable in sharing ur data.
regards
chandan
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Does anyone have tutorial for Abaqus Additive Manufacturing simulation?
I want to simulate a 3d printed item (material of item = ABS plastic) and conduct stress analysis on it. However, I hardly can find any tutorial from Youtube and Google.
Does anyone know where to search for tutorials?
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Check the following link :
This link will direct you on the usage of Abaqus in the additive manufacturing
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How I can proceed for finite element modelling of micro drilling on Additive manufacturing part. Please provide your valuable suggestions.
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Salah Uddin Thanks sir
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Hello All,
I came across an additive manufacturing heat transfer FEM problem. In this problem, in each time step, a material is added to the current geometry. So, an amount of mass with a defined temperature is added to the whole geometry.
I heard about the Abaqus AM tool, but I would like to develop my own code. So I am wondering about the best method to solve this FEM? How can I define and update the stiffness matrixes? How can I reduce computational costs?
I appreciate any help or tip!
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About the stiffness matrix size: you can do it, but it is just a purely numerical solution (no science behind) if you make your steps independent (I mean if you move from step n to step n+1 and between those 2 steps there is a dimension change, export results from step n and make a transfer to a new model corresponding to your step n+1 putting zeros wherever there is no data from the previous step results and add whatever you want to add in the formulation of the initial state of your new calculation, ie the n+1) however, about adding mass, yes you would be infringing the fundamental law of mass conservation if you consider your system at step n and step n+1 the same, this is why I propose to numerically separate the model into one corresponding to step n and one other to step n+1. I hope I explained well my point
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Looking for a motivated Ph.D. candidate to work in the field of additive manufacturing with the background of mechanical engineering and material science.
Deadline for application: February 14, 2020
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Dear sir,
during my master degree my research work was on laser additive manufacturing.
i would like to pursue my doctor degree on additive manufacturing because of my previous work.
if there is any vacancy on additive manufacturing please let me know.
thank you
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The paste is designed to be dispensed from a syringe with a small nozzle. The paste is composed of highly viscous fluidic phase, and several types of solid spheres with different densities. The fluid phase, should evaporate as a function of temperature, or at least change its viscosity as a function of temperature (first option is preferred).
Please find attached pictures of the paste.
I was wondering if I should use Smooth-particle hydrodynamics (SPH) method?
The goal of the simulation is to simulate slump phenomena as a function of paste composition, pressure distribution, deformation analysis, non-Newtonian analysis, # of printed layers, etc..
Thanks,
Gilad
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You may want to check answers to a somewhat related question at this forum for its possible interest: «What are the most important parameters controlling the extrusion of pastes?»; https://www.researchgate.net/post/What_are_the_most_important_parameters_controlling_the_extrusion_of_pastes
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I am working on Numerical Simulation for Cold Crack prediction in additive manufacturing and looking for a way forward to do FEM simulation with ABAQUS. Generally, cold cracks produced in the presence of hydrogen so I wonder if there is a straightforward solution for hydrogen diffusion or crack prediction with FEM. Thank you in advance
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Rakesh Kumar from Imperial College London may help you out.
Vishal Singh, IIT Ropar, India may also be helpful to you.
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Achieving a desired surface roughness for fatigue specimens is one of the common challenges, particularly when you have to perform a large volume of tests (for instance, 400+ fatigue tests within a short span of time for SN curve development). As-machined specimens from CNC are minimum 0.8μm Ra, however most standards recommend a minimum of 0.2μm Ra. So, it is almost impossible to polish manually and maintain same quality in a repeatable manner. There are some facilities that can perform automated polishing, however, it’s expensive! Moreover, most automatic polishing facilities are in the circumferential direction, but according to relevant standards polishing should be along the length of the specimen. Now, coming to my question -
Q. Let’s say we performed the tests for specimens with 0.8μm Ra (it can also be 1, 2, or 5 μm). Is there any accepted/practiced methodology to represent the results as 0.2μm Ra, i.e. by how many factors fatigue life would have improved if specimens were of 0.2μm Ra?
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Hi Dibakor Boruah,
You might be aware that fatigue is statistical in nature i.e., there exists a large variability in the fatigue-test results even when all the specimens are tested under identical conditions. With this kind of statistical nature of fatigue, I believe that even if all your specimens have 0.8μm Ra, the results wouldn't be identical. In those cases, I am doubtful that how can we expect that we can do the representation of results when your specimens have 0.2μm Ra? As far as my knowledge is concerned, I think there might be no such methodology to represent results between specimens when you have two different surface roughness values. And there is no other thing like we should not use polishing machines which do in circumferential direction and only we should try along the length of the specimen. This might be the case, when you are polishing with hand (manually), where it is only recommended to do polishing along the length. I suggest that you can try with what ever automatic circumferential polishing machines you have to achieve the desired roughness level. Please correct me if I am wrong.
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Hello everyone
I use a metal powder as the filler to a thermoplastic polymer matrix. Therefore, I wonder if there are any changes such as the molecular weight distribution, occurring in the structure by adding the filler metal powder?
My regards.
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Dear,
Some pigments can cause property modifications. I have tested PLA with different colors, and they have different tensile strengths.
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I want to download Abaqus AM modeller but I couldn't find it. I ask anyone who has this file please inform me.
Thank you.
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It is there but you need to search through the documentation of the latest version 2020 or 2021
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I don't see any inherent benefit of e-beam over SLM? Since you need a high vacuum for the e-beam and also need a very high-temp heat bed to consolidate the powder to create a conductive path for the e-beam; but it seems it's so widely used for titanium alloys even though titanium can be printed via SLM very well.
Is it just because the process parameter development has been around for much longer?
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Another reason for the diffusion of the technology is the high build rate of the EBM maccine, which allows to realize parts at lower costs, moreover the high superficial riugosity, due to the process (mainly due to the less focused beam of the laser and higher granulometry of the powder), is excellent for the osseointegration and makes the parts made in EBM perfect for the production of prosthesis.
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I need to simulate the laser path with different patterns for metal additive manufacturing along with deposition of materials in ANSYS. Is there a way to do it?
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For simulating laser path in Ansys Workbench, download 'Moving Heat Source' extension from the Ansys store.
This video will be helpful:
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I am working on FEM Simulation of Crack Susceptibility in PBF additive manufacturing. Perhaps, Could not find a way to evaluate residual stress threshold value for crack prediction through numerical simulation. I look forward to your answers
Regards,
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plasticity induced crack closure (PICC) concept and three dimensional (3D) finite element method (FEM) were used to study the effect of compressive residual stress field on the fatigue crack growth from a hole. Furthermore, a new methodology on the basis of a correction factor was presented to increase the PICC precision. The result obtained was compared to two dimensional (2D) FEM, superposition method and Liu’s experimental data. To simulate the elasto-plastic behavior of the material, isotropic hardening was assumed and the Von-Mises yield criterion was implemented. A 3D mesh was built using eight-node hexahedral elements and one half of the specimen was modeled. The simulation results were fairly well correlated with experimental data. Furthermore, the 3D elasto-plastic FEM predicted a slightly smaller fatigue life than a 2D plane stress FEM. Applying the modified PICC method reduces the 3D FEM fatigue life prediction errors.
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Hi, I am trying to model the WAAM (wire-arc additive manufacturing) process in ANSYS APDL. The solution didn't throw any errors, but the result is a bit confusing.
The graph in the figure is node temp (element no 12) vs time plot. The graphs show a temperature rise well before it is activated. Ideally, the temperature should rise when it is activated.
Following is the solution setup for the model:
convection load to all external nodes > killing all the elements > transient thermal, newton raphson method,> initial temp 303 K> in do loop activating the elements sequentially> applying 'f' load (heat) to the active element> solve> delete 'f'
Any suggestion will be helpful.
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Please see the nodal heat flux results for any time-step before the killed elements are born.
The heat flux/flow for these nodes should be zero or negligible compared to the heat flux of the nodes of live elements.
If they are not zero, then I guess the apdl code needs to be rechecked. Otherwise, if you are doing the analysis as per some reference paper, and your results approximately match that paper, then I guess it is ok.
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How to determine the the fatigue values at high stresses ? Because the endurance limit for my material is round about 480 MPa. and the yield point is about 660 MPa.
When I try to find the values in fatigue region at high stresses let's say above 550 MPa and 600 MPa, the material fails immediately after it starts to run and i could feel the heat dissipated. Does it mean anyway that its not possible to have fatigue limit or is it fine to just show the endurance limit ?
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In fatigue experiments the material and its microstructure plays a vital role. Its better you tell which material you are using and its composition. Also let me know whether you are using axial fatigue or rotating beam fatigue ,
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I am working as a research intern on the above-mentioned title. Any leads, guidance, suggestions, help are all accepted.
Towards the topic,
To deal with new Additive Manufacturing challenges, there is a great need to train workers on this new manufacturing technology through efficient learning programs and tools near to the factory. The aim of this topic is to explore it for the creation of an attractive lesson on key AM processes. The proposed scenario will focus on the configuration of machine parameters by defining the background model that connects machine/process parameters to product characteristics. Based on that, virtual reality conception software (UNITY) will be studied to analyze how the model can be implemented in a practical scenario.
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Mika Stapelfeldt Thank you for your valuable suggestions, I will look into those and make a note of them.
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Actually i started working on additive manufacturing of bone impants in specific humerus bone . I did communicated couple of papers on this area , due to pandamic the work is not going in right direction . I want to incooperate Robotics at this step in stead of going head with the work . What sort of robotic process can be brought here
or any suggestion to combine bone implants to robotics.
I am a mechancial Engineer , not good at surgery parameters so surgical robotics, hip replacement are not my cup of tea. so what suggestion can be given to combine Additive manufacturing of bone and Robotics .
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Hello everyone
In the case of the FDM process, while the polymer filament extruded from the narrow section of the nozzle, we know that the shear-thinning _ concerning the temperature higher than "Tg" and lower than "Tm", and also increasing the shear rate_ effects on the polymer melded fluid. Nevertheless, does this non-newtonian behavior of the polymer melded fluid affect the mechanical and physical properties of the 3D printed sample?
Best regards.
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The breakup of polymer chains during the strain rate changing cycles is not reversible which will change its mechanical properties. The degree of such breakup depends on the specific cycle settings (e.g., strain rate, duration of application, temperature, etc.) and qualities of polymeric, which results in inconsistency. Such behavior is very common in polymeric non-newtonian fluids.
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Dear colleague,
I am working on Co-based superalloys produced by Additive Manufacturing, and I really am in need of using PANDAT Software to design and predict my alloy thermodynamic, solidification, precipitation behaviour. I would like to know how can we have access to " Pandat™ Co-based thermodynamic database PanCo2020"? It should be mentioned that I had checked the Pandat website, but could not find anything in this regard. Also, It would be my pleasure and appreciate any collaboration in the project and out coming papers.
Thank you for your time and consideration.
Best regards, Mohammad
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The software and databases are not free. There is a student version you can download but the databases are rather limited.
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I am trying to simulate the deposition of a single extruded path using element birth and death technique. In each load step one element is activated. The initial temperature of the activated element (in the current load step) is to be the nozzle temperature. The initial temperatures of the previously activated elements is obtained from the results (temperature field) of the previous load step. The steps adopted in the model are as follows:
  1. Creating & meshing the 3D model (of a single extruded strand of length=50mm)
  2. Deactivating all elements (using EKILL)
  3. Setting up the solution
  4. Activating one element
  5. Specifying initial condition on nodes
  6. Specifying boundary conditions (Convection load on exterior node)
  7. Specifying the necessary load step options and solving.
  8. Repeating steps 4 to 7 for each activated element (using *DO loop).
I am facing the following issues:
  1. The analysis runs properly only for the first load step, in that the decrease in temperature of the element is in accordance with the convective loading applied on it. But from the second and subsequent load steps onwards, the temperature distribution obtained is not proper. When the second element is activated, the face of the element exposed to ambient air has a constant temperature = nozzle temperature even though convective load is applied on this element. Element numbers 3 and beyond, remain entirely at the constant temperature = nozzle temperature. Note: If however, each load step is run in a separate file (with all other parameters constant and by reading in the solution of the previous load step as the initial condition), the results of each load step are in accordance with the boundary conditions and loads assigned to them. I am unable to identify what's causing these improper nodal solutions when solving all the load steps in a single file. Am I missing out on any crucial step in my code? Why is there a difference in nodal solution between these two approaches (solving all load steps in one file v/s solving each load step in a separate file)?
  2. When assigning initial conditions, the temperature distribution from the previous load steps can be read (using LDREAD) for the previously activated elements. However, I am unable to separately provide the initial temperature to the element activated in the current load step. The following warning message gets generated : Initial Conditions not allowed after first Load Step. Currently I have managed to avoid this issue by assigning a uniform temperature (equal to the nozzle temperature) at the beginning of solution for all the nodes (of activated as well as deactivated elements), but I am not sure of it. Is there a proper way to separately provide the initial condition for element activated in the current step?
  3. Also, is LDREAD command the proper method for using the results of the previous load step as the initial condition for the current step?
Since I am new to ANSYS, any suggestions w.r.t these two issues and help in identifying the mistakes in my code/approach will be greatly appreciated.
The relevant screenshots from APDL as well as the code have been attached for reference.
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Ansuman Sahu , Regarding query no. 2 in your question,
In your code, after setting the initial temperature by TUNIF, set TIME as 0. Then start a *DO loop.
The loop should run from 1st to the last load step.
Inside the *DO loop, activate (EALIVE) the required elements sequentially. To achieve this, your element numbering should follow some ordered series in the zone where they would be sequentially activated.
Then apply your boundary conditions.
Then increase time by the time step size.
TIME_NOW=TIME_NOW+0.5 !!times step size=0.5
TIME,TIME_NOW !!set TIME to the current time
DELTIM,0.5,0,0 !!! Set min and max time steps
The solve inside the loop.
/STATUS,SOLU
SOLVE
Don't use LSWRIE/LSSOLVE. It may not work EALIVE/EKILL
Delete all loads in this step
End the loop
!!! In this way, your solution of each step would become the initial condition for the next step
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Hi,
I am trying to model metal deposition by the welding process. The results from the previous load step will be the initial condition for the next load step. Following are the step adopted for the model:
  1. creating the entire 3d model
  2. meshing the entire model
  3. killing the elements to be deposited
  4. setting-up the solution
  5. activating elements (one at a time)
  6. applying load and boundary conditions
  7. solving the model
  8. delete all surface load
  9. repeat step-5 to 8
Issue:
  1. the result for the first load step is reasonable as shown in the figure attached, but for the subsequent load steps are meaningless
  2. result of the last load step is only available in the general postprocessor
  3. time history postprocessor shows error
I have attached relevant files and code.
If any suggestions, please let me know.
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Hi Kumar Ujjwal , I had a doubt regarding the code, since I am new to ANSYS. I am trying to model the fused deposition modelling (FDM) process using element birth and death.
To use the results of the previous load step as initial condition for the current load step do we need to read in the .rth file using these steps: Main Menu>Solution>Define Loads>Apply>Initial Condit'n>Temp from ANSYS or by using the 'LDREAD' command?
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I understand there are a lot of software programs that can simulate DED by going through specific modeling, simulation, and commands. For me, that was time consuming and results were not accurate. I am asking if there is a specific software that already has the DED process included.
For example, I have found some programs that come automatically equipped with modules/wizards to directly simulate FDM and PBF. However, I was not able to find one the has a module/wizard to directly simulate a DED process.
Any advice would be greatly appreciated!
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The following software is capable to make simulations for the Direct energy deposition (DED) process :
1. Autodesk Netfabb (Ultimate version), https://www.youtube.com/watch?v=E4WM6eSdPlo
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If we will fabricate 49Ni-51Ti and want to train the product to actuate at 40C , then how we will follow the procedure in 3D printing?
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Hi, i am trying to simulate multilayer metal deposition using 'element birth and death' technique.
I have glued the three volumes ie substrate, layer1,layer2 as shown in figure. Then, i am trying to kill the layer2 to simulate the deposition of layer1. At last, i will activate the layer2 and apply the load on the layer2.
Am i thinking in the right direction?
There are 43 loadsteps in each layer so i am using do loop but, i am getting following error,
Where do i place 'ekill' command in my code??
i am attaching the snapshot of the APDL script after meshing.
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For the past few months, I was busy with some other work, so the late reply.
I followed your suggestions and ran the simulation but still running into some errors:
  1. Firstly, I activated only one element and applied the heat flow; the result came fine.
  2. But, when I ran the whole 'do' loop the results doesn't make any sense.
  3. Also, in the post-processor there only last load step that can be read.
  4. In time-history post processor it shows error.
I am attaching the relevant files. If possible, can you look into my code a give your expert advice?
Best Regards
Kumar Ujjwal
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Ansys 19.2 R2 and 2020 R1 versions of Additive Manufacturing Workbench is convenient for powder-based Additive Manufacturing processing. However, in this workbench, there is a machine parameter setting dialogue box and this parameter setting dialogue box has not included the laser power parameter. Without laser power, the powder material will not melt. So, how to add laser power in the machine parameter setting?
Thank you very much for your cooperation
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Dear Dr. Betim Shabani, thank you very much for sharing your idea. It's informative directions.
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Dear Sir/Madam,
I have obtained my doctorate degree on the topic “Experimental Studies on Friction Stir Welded Joints of Magnesium Alloy”, from Inder Kumar Gujral Punjab Technical University, Kapurthala (Punjab). So far, I have published five research papers in SCI journals.
I want to continue my research on implementing the concept of weight reduction in automotive industries by using magnesium and other new lightweight alloys. I am looking for a postdoctoral fellow.
Could you help for the same?
Thank You.
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Dear Dr.Singh,
Firstly, Congratulation for Ph.D. Degree.
Currently, many universities are offering for postdoc study.
In India, you have a good opportunity to work in a research center in IITs so find the potential supervisors who are working in your search area and send them an email.I think IITM and IITB will be best for you to continue your postdoc study. these colleges are also offering a good salary.
In overseas, Germany and Canada are the best option for you as per understanding. visit the Mendeley website and find postdoc opportunities. In addition, you can also email the potential supervisor reading your interest. If they have funds then they will definitely respond to you.
All The Best!
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Dear all,
i have found lots of books on additive manufactuting but very few lecture notes (ppt) files.
I am doing a 3d printing project as my thesis and have to present the historical background etc. I surely am not looking for copying stuff from other ppt's but seeing different versions will surely give me a broad idea for presentation.
I have also read books about additive manufactring but seeing the most common topics valuable for a presentation would ease my work for the first slides of my work so I can focus more on my real project.
Any lecture notes about 3D printing you could share (which are not available freely available on google search) ?
Many thanks in advance.
Cheers
Alev
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Dear Alev Sonmez, Use this textbook. I hope it helps you with your article.
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Additive manufacturing or digital printing are known to produce porous and lower than bulk density products. How can we produce highly densified zero defect products using these techniques ?
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The quality of a product is dependent on both facilities/equipment and manufacturing processes. Any error or disorder in facilities and processes can cause a catastrophic failure. To avoid such failures, a zero- defect manufacturing system is necessary in order to increase the reliability and safety of manufacturing systems and reach zero-defect quality of products.
General manufacturing challenges for AM lies in the development of self-contained, robust, user-friendly, safe, integrated system to provide required deposition scan motion, and speed, high feature-volume resolution with concomitant energy for part fabrication and dimensional control.
Other challenges pertaining to AM products are surface finish, part size, variations in product quality from machine to machine and between batches of productions, and a lack of fundamental understanding of the impact of operational variables on part quality.
One of the major challenges for zero defect manufacturing is the analysis of massive raw datasets. This type of analysis needs an automated and self-organized decision making system.
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What software/tools (commercially or others ) are you know for cloud manufacturing?
I want to find an effective way to bring production service providers together in one platform (Cloud Manufacturing).
The research domain can be general or restricted by one or some domain.
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Dear Sir,
Cloud manufacturing software gives manufacturers full control over inventory control, sales order management, quality control, and material requirements planning from anywhere and with any device connect to the Internet. These cloud-based systems won’t be installed on your own computers, so you’ll save time on implementation, updates, and IT support. Since these systems are web-based, you can also access the system from any operating system whether you have Windows or Mac, or are looking to access with a mobile iOS or Android device.
Some Cloud manufacturing software are mentioned below:
Plex Cloud ERP is a cloud manufacturing ERP software that helps lower costs while scaling seamlessly with your business. Katana MRP, MRPEasy, Acumatica ERP, Odoo, NetSuite ERP, OptiProERP, Sage 100, Rootstock Cloud ERP etc.
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Last time I was asked about simulation software to analyze the effect of shrinkages of plastic powder materials. Currently, an additive manufacturing process is what I find suitable for my research. Suggest me kindly, the type of software’s with its module that capable of analyzing shrinkage of metal powders in the Additive manufacturing process?
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Dear Eyob,
I simulated the shrinkage of the powder for simulating Additivr manufacturing process using Abaqus and defining a pseudo thermal expansion coefficient. You can read more about the method in my paper
Powder bed properties modelling and 3D thermo-mechanical simulation of the additive manufacturing Electron Beam Melting process
Best regards
Manuela
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I read in some articles that it has already been done with Netfabb but I'm searching for a free software.
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I recommend using Ansys, because there are many video tutorials that you can find. My friend Dong Van Dat also use Ansys for his studies. But, for studying Kinematics and Dynamics motions, you can use RecurDyn software to analyze it.
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I am trying to capture the XRD intensity peaks for a part made up of nickel alloy. When I try to capture the peaks, I am unable to get them. Can someone help me out why is this phenomenon happening and what are the reasons behind it? If any literature available with relevant to the non availability of intensity peaks in XRD, please do help me out.
Thanks in advance
Hemnath
#XRD #MetalADDITIVEMANUFACTURING #Residualstress
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Your description is superficial; more details are necessary.
Are you trying to get the X-ray diffraction over a surface with elevated rugosity?
Are you sure the X-ray beam is scanning the desired surface area?
I understood the experiment is "in situ," which may not represent the minimum necessary diffraction condition for a reliable experiment.
Your nickel alloy may have texture, and you are probing an inappropriate angular range.
Some alloys are specifically designed to have an amorphous characteristic; it fulfills industrial needs, be sure it is not the case, usually obtained by quenching.
Sometimes, to prepare the sample, even metallic ones, a reliable X-ray setup measurement is usually necessary, by milling the alloy, ball orbital milling that may or may not be ideal condition.
Besides, there is the possibility to modify the measurement conditions with a higher voltage or current to have a better signal; the operator knows how much it is safe to use. You are increasing the power of the beam.
X-ray in alloys is well described in the literature. Expend some time searching some specific papers based on the history of your sample.
Best regards
WNM
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Hello everyone
As we prepared a composite in filament format and print a sample, how could we control the distribution of reinforcement non-continuous fiber or particle on the deposited layer path?
Best regards.
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Thank you for your contribution, yes. I mean the filament composites. when we produce a filament by adding non-continuous fibers or particles, by melting filament in the heat zone of the nozzle head of the 3d printing machine the additive materials change their positions in the solid filament. Hence the additive materials don't have a uniform distribution in the deposited layer. Therefore I'm looking for a way to achieve good distribution in the deposited layer. Yet no success was achieved.
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I've seen some videos where a sand casting mold is being 3D printed using a 100W CO2 laser and galvo scanner.
450nm fiber coupled diode lasers are also available up to 1.5kW and quartz sand reflectance is apparently only around 10% at this wavelength.
I can't see why this printing is not better with a more reliable blue diode laser. I wonder if anyone else can?
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So, my trials showed that melting sand is possible with a blue laser diode. However, only the natural type of sand due to its hematite content. The absolute minimum power density is about 4W/mm2, but this will also depend on the amount of Fe2O3 content.
As the temperature reaches 1700°C, the hematite will convert into black magnetite which has lower absorption at the blue 450nm wavelength, further heating will need a larger amount of power.
Heating pure hematite could be even more interesting..
The photo showes a piece of originally red Australian desert sand melted together by the intense laser spot.
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Hello everyone,
in the context of my dissertation I am trying to find out how product development will change with regard to additive manufacturing. Will product developers have identical workflows in 5-10 years, or will parts mainly be calculated and geometry created automatically?
In order to better understand these and similar questions, I developed a short survey, which mainly includes the use of alternative programs for geometry generation and the product development process itself.
I would be pleased if you would take a short time to answer the survey.
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Sebastian Kuschmitz completed the questionnaire, all the best to you with your research.
Best Regards
Martin
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Hello everyone,
I'm a new PhD student and I'd like to expand my 3D printing community. My research is around Multi-Material Multi-Material Additive Manufacturing for the creation of turbine blades.
Please comment or follow so I can follow you if your research is around anything 3D printing/additive manufacturing related; hybrid printing, multi-material printing for example. Research around materials science around plastics, ceramics and environmental materials, software and systems around 3D printers and turbine blades also.
I'd be grateful if you could comment or follow so I can follow you and your research.
Thank you very much :)
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Muhammad Harris Check Anisoprint, its a open system in continuous fiber printing, here you have control over polymers (any polymers) and slicing software. However, similar to Mark, carbon fiber are propriety material from Anisoprint...however, with bit of experience you can manage to print Mark fibers as well...
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I have references for SLA and material jetting processes but nothing for SLS or jet-fusion. Any assistance would be appreciated.
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Thank you Brandon for those references.
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Hi all,
I am trying to reduce the particle size of my FeGa powder. I am using a SPEX 8000 ball mill and my powder is currently at 40 - 200 microns. I would like to get it to 40 - 60 microns. Does anyone have any recommendations for how long I should mix it for?
Any other recommendations would be greatly appreciated, including resources for me to read.
On a side note, is there an easy way to crush an ingot into powder? There must be a better method out there than the one I used.
Thanks in advance!
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Due to the existing of the limited surface area(S) for each materials, and please decide the suitable milling time by experiments.S=S(infinite time)*(1-EXP(-k*E))
E:grinding energy
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Hi, I would like to lead my research in additive manufacturing by welding and joining.....is there any researcher interested on intellectual ground to collaborate for the research?
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yes I am interested to work in these fields
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What are the benefits (if any) of processing NiTi (nitinol) through: laser powder Bed Fusion (LPBS) /Direct Metal laser Melting (DMLM) vs. Extrusion-paste-printing followed by Sintering where the powder is contained within a viscous organic binder?
Can any of these procedures be followed by a HIP process?
Thanks,
Gilad
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If you will follow the extrusion-paste-printing procedure, then you will get disseminated regions on the surface after a few numbers of actuation-cycle. This is due to local concentration. For homogeneity behaviors, better to follow the LPBS/DMLM.
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I have to use different software such as
- Solidthinking Inspire
- Creo 6.0
-Simens NX
- Optistruct.
so which one is better for on point of result and surface finish.
thanks
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In my opinion, the available commercial topology optimization software has not been developed as well and only suitable for solving simple and conventional industrial topology optimization problems.
For example, there are many shortcomings in problems of material design such as the optimal design of functionally graded materials, simultaneous design of structure and microstructure, multi-material topology optimization, design of fiber orientation in composite structures, design of meta-materials and auxetic structures, Origami, Kirigami and cellular structures.
Also, most of the software does not cover all of the complex industrial objectives. For example, the crashworthiness topology optimization is only covered by LS-Task that uses hybrid cellular automata (HCA) which has the assumption of uniform energy absorption among all elements of the structure that is not a correct assumption for thin-walled structures. Similarly, solving TO problems in design-dependent loads, random and non-linear vibration, maximization of multiple eigenfrequencies, wave propagation, etc. would not be possible by software packages.
The codes recommended by Daniel Gert Nielsen are so useful for academic and research applications because they are implemented to solve benchmark problems in TO while not solely suitable for solving complex industrial problems in large scales.
To conclude, there is no “Best Software” in general for all problems. If you are looking to solve conventional simple engineering problems, I would recommend “Optistruct”, because it can consider more objective functions in comparison to others and has the equivalent static load (ESL) method for solving explicit dynamic problems. Also it is able to present lattice topology optimization. But if you are looking to solve more complex problems, you must choose methods from the state-of-the-art, implement the code and connect it with one of the commercial FEM solvers such as ABAQUS, LS-Dyna, etc.
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I need to calculate the content of NCO in an isocyte (prepolymer) which I will then have to react with a polyol, to give a polyurethane, I would like to know if it is possible to calculate the content of NCO via FT-IR (currently we carry out this analysis by titration); in order to make it react that then the isocyanate can react completely with the polyol, and therefore maintain the ratio 1/1
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Try calculating the band area (FTIR) - NCO group.
Best regards,
Jéssica
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I am looking for FEM framework for cold cracks prediction in additive manufacturing. How to establish numerical criteria?
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Muhammad Qasim Zafar , these problems are common and fundamental, so you can find them in welding theory books and molybdenum welding guidelines. Good luck!