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Dear all
Hope you are doing well!
What are the best books in Materials Science and Engineering (Basics and Advanced)? Moreover, what are the best skills (or materials topic related) that materials scientists have to develop and to acquire?
Thanks in advance
^_^
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Dear all, following a list of interesting books. My Regards
- Fundamentals of Materials Science and Engineering: An Integrated Approach, William D. Callister, David G. Rethwisch, 5th Edt (2015).
- Materials Science and Engineering: An Introduction, 10e WileyPLUS NextGen Card with Loose-Leaf Print Companion Set, Callister Jr., William D., Rethwisch, David G. 10th Edt (2018).
- The Science and Engineering of Materials, Donald R. Askeland, Wendelin J. Wright. 7th Edt (2014).
- Materials Science and Engineering: A First Course, V. Raghavan, (2004).
- Foundations of Materials Science and Engineering, Willaim Smith, Javed Hashemi, 6th Edt (2019).
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I want to Create Surfaces/sets from wireframe 2D Sketch in .Iges format to do a 2D analysis of a Ceramic material. I am using ANSYS Workbench to create a mesh for my geometry. The .jpg file is attached. The .iges file imported from a different source where the sketch had been created in wireframe 2D, contains splines and lines, the closed splines and lines represent the crystals and the rest is the matrix. The crystals had been indicated with C and matrix with M in the image respectively.
Could you provide some information on how should two surfaces/sets can be generated in ANSYS so that meshing can be done afterward?
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I don't use ANSYS or any other commercial software. I am from the generation that if we needed a computer program to perform a given task, we had to write one. In the past 60 minutes I wrote a program to triangulate the polygons shown above. The results are attached. I could have put a mesh everywhere there isn't a polygon.
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Hello everyone,
I'm currently doing some DTA analysis on two phases of the same ceramic material, one is fully crystalline and the other fully amorphous.
When I work with the crystalline one I have a melting peak, with a clear area I can integrate if I want to.
But when I'm working with the amorphous one, I don't have a peak anymore but more like a transition, with no distinct area (similar to a reversed glass transition in a way).
Why don't I have a proper melting peak on my amorphous material ?
The same heating rates have been used, with really closed mass for the samples.
Thank you for your help,
Julien
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Crystallization of silicate glasses occurs at temperatures significantly exceeding their Tg points. If for most silicate glasses the Tg temperature is about 500°C, then crystallization begins at least 800°C, and in some cases at 1000-1200°C. In addition, there are silicate glasses that do not crystallize at any temperatures.
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For different purposes, molten metals will be in contact with a ceramic material. For example a furnace nozzle guides the melt flow to the mold is usually made from a thermo-chemical resistant ceramic.
- However, in the case of Mg metal, chemical reactions and temperature drop are very fast.
- Beside, mechanical strength and elongation must be high enough to suffer mechanical shocks.
- Moreover, machinability and density of a ceramic material must be good enough to form in the desired shape.
I will highly appreciate if you let me know your answers and reasons in this regard.
#Magnesium
#Oxidation
#Flamability
#
Best regards,
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Aluminum titanate ceramic can be very useful for the application:
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I have synthesized a titanium-based ceramic material (Titanium Carbide) by high-temperature synthesis. But I am getting Oxide peaks while performing XRD analysis. Is there any way to remove the unwanted oxides from my sample? If so how to do it. Kindly enlighten me
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Any alundum pipe passes oxygen like a sieve (unless, of course, it is a single-crystal sapphire), i.e. it is very gas permeable, especially at high temperatures. In addition, it is very fragile and when heated / cooled, microcracks appear in it, which can only be detected when filling a plugged, verticaly installed pipe with a solution of rhodamine (pink stripes appear on the outer surface - be careful, rhodamine is washed off the skin after about a week...). In addition, at high temperatures, all impurities in alundum (silicon oxide, sometimes oxides of iron, chromium, and titanium) also appear in the samples. Usually, we mechanically removed the surface layer richest in oxides and other impurities from the resulting "tablets". But, I repeat, we have never synthesized titanium carbides in alundum, but only in a vacuum furnace with substrates of metallic tungsten (sometimes even tantalum).
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For O1s, there are two peaks, 529.6ev and 533.3ev.
529.6ev can be corresponding to Zr-O. But 532.3ev, I don't know how to explain it.
Consult relevant literature, there are two explanations.
The first, It may be Si-O, but there is no Si element in my material.
The second, It may also be chemically adsorbed oxygen, but is this possible in ceramics materials?
I am puzzled by the analysis, hope I can get an answer about it.
Thank you
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Dear David J. Morgan
Your suggestions are very important and helpful to me, thank you very much.
I rechecked my C1s spectrogram. Some organic matter is indeed present, but its corresponding intensity is very low. Similarly, I also re-compared the full XPS spectrum and did not detect Si.
Regarding the polishing, I used diamond sandpaper and performed 2-3 ultrasonic cleanings afterwards.
So I have re-prepared the sample in question and waiting for new test results.
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Thermal behavior of ceramic materials
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You have 2 possibilities:
1- Calculation : Temperature of the Crucible should be close to adiabatic combustion temperature of the biomass which could be calculated if you have basic composition of biomass material (in terms of raw fuel - H2,C, CnHm, O2, S...) and through heat balance of the furnace: Temperature of Furnace is result between energy flux (enthalpy) provide by biomass combustion minus heat loss (fatal heat loss due to waste flue gas exhaust and heat losses from furnace walls)
2 Or You can do measurements : 2.1 Direct measurement with IR camera of the furnace walls temperature or with thermocouple place through the wall just under internal surface of wall refractories and 2.2 A high temperature thermocouple into combustion crucible or Suction pyrometer prob juste under Biomass combustion
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Consider a small tube made of polymer or ceramic (inner diameter of about 3mm, outer diameter of about 1cm, and 5cm length), inside which a high-gas pressure should be generated in a short time (few microseconds). How can we measure the maximum gas pressure that the tube can withstand before it breaks or deforms, even before starting the actual experiment?
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Dear Mohamed A. Abd Al-Halim, please check the following links. My Regards
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My goal is to create a layer of Lead Zirconate Titanate, or other piezoelectric material, deposited on the surface of a PFTE Teflon tube. What are some good methods to accomplish this task?
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If the PTFE tube is quite large (more than 30mm in diameter) then you can try applying the ceramic layer by plasma spraying. It's not easy, but possible.
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Why does a Cole-Cole plot display a downward slope?
After plotting the E'' vs E', there is a particular composite that has the opposite trend of others. Attached is the image. Thank you
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Based on the plot, the dielectric loss factor has the lowest value and highest dielectric permittivity at low frequency part.
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Dear all,
I am investigating the corrosion resistance of ceramic coating (deposited by PVD process) on Stainless steel samples using Gamry Instrument with parameters OCP (77.78 mV conducting before tafel curve), then scan rate = 1 mV/s, Potential = -0.5 to 0.5 Vs OCP in 0.5M NaCl environment. During starting of tafel curve, there is overloading error within 3-5 minutes and also coating was seen peeled off at the point of contact/interface between solution and Coating having area .022 cm2.
Kindly suggest the best possible solutions to overcome this problem.
Thank you
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Dear Dr. Shashi Kant ,
I suggest you to have a look at the interesting Application Note CORR-1 by Princeton Applied Research, available at:
My best regards, Pierluigi Traverso.
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What is the best cement, and the temperature required to ensure a good bond ?just normal alumina ceramics. I wish to bond two pieces thoroughly which would withstand high temperatures say 800  to 900 deg C.
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I've used Aremco Ceramabond 503VFG to bond together alumina pieces. This was shear tested after aging at 750C/100 hours along with 3 other ceramic adhesives and it had a mean strength of 40 MPa. It is rated for 1650C. Aremco has other high temperature adhesives and if you contact them, they can help.
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In the (electro-) conducting materials, as I know, there is an energy gap between the valence band (VB) and the conduction band (CB) that can be brought to or near-to the Fermi level by doping (p-type or n-type dopant).
But ( My question is ), If I want to design a (semi- or super-) conductor's materials (inorganic or polymeric) , Which properties would I look for? and, also, Which characterizations would I consider for the properties' investigations? What are the requirements for the materials' property (with regard to its band structure) to achieve the considered structure-property relationships (or requirements ) for the preparation of the conducting materials?
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Indeed Dear Ahmed MS Dawelbeit it is a very interesting and subtle question, refer to it as a localization phenomenon is one way since electrons can be seen as wave packets that can be or not well defined within the structure (metal, either metallic polimer).
In general, we have a kinetic criterium with three well-defined regions, the product "l . kF", since we understand localization as the absence of diffusion of any kind of waves in a disordered medium.
Please check for the case of metallic polymers, the following reference:
Alan J. Heeger, 2003, The Critical Regime of the Metal-Insulator Transition in Conducting Polymers: Experimental Studies. Condensation and Coherence in Condensed Matter, pp. 30-35
it is very instructive
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Hi all,
I wish to know about a common problem faced by most of the researchers who are dealing with ceramic materials that my ceramic powder is sticking with the balls after the operation. can someone suggest me to get some resolution to this problem?
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Good afternoon everyone, I want to make a calculation of the optical properties of a perovskite-type ceramic material, but I present the following questions that I would like to help me clarify:
1. In order to do the calculation of the optical properties, I must first do the minimization calculation?
2. My great doubt is referring to some INCAR parameters when I am going to calculate the optical properties, they are: IBRION =? ISIF =? LORBIT =? LREAL =? LWAVE =? NSW =? PREC =? 3. Can I calculate the optical properties with PAW-GGA?
I appreciate your attention and I look forward to your comments
regards
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Dear C. Deluque,
Regarding your first question, I would say the answer is "yes". If you want to study how a material interacts with light in its ground state, you need the structure of the ground state. After that, the geometry of the excited state may change... But that is a different story (which may be important for processes such as fluorescence or phosphorescence)
Regarding the INCAR file. I think none of the keywords you mention is going to affect the results. Of course, I would perform a single point calculation of the optimized geometry (IBRION=-1), and maybe further analysis of the DOS (LORBIT=11) can be useful, but... I recommend you to see the "LOPTICS" keyword:
And yes, you can use PAW-GGA, although usually hybrid functionals are better for (electronic) excited states.
Hope it helps,
Fernando
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I came across an article that uses heat treatments to determine whether or not the surface charge introduced by contact electrification on a ceramic material is due to electron-transfer mechanism or ion-transfer mechanism. I was wondering if ions can be removed using heat or what other method can be used.
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Hi Serena Armiento,
Yes, it can, this be the ions transfer through the ceramic structure.
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On a synthetic graphite tube production line, this type of defect, similar to scales or the beginnings of cracks (cf. photos), appears regularly, including on unimpregnated tubes, just out of the oven (on the photos, these are tubes that have been impregnated and then brushed with traces of resin at the bottom of the scale). We noticed that our graphite had an abnormally high Fe content (a supplier problem). Do you think that these defects can come from a cast iron inclusion (the carbon of the graphite + Fe) formed locally during the graphitization process? Can such an inclusion at this scale (0.5-2mm) lead to surface flaking? If not, do you have any ideas on the origin of these defects?
Thank you very much for your answers and time,
A french materials engineering trainee in need of knowledge
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sure it maybe
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I want to make slurry for aqueous tape casting of alumina (500 nm avg. particle size) using PVA binder and PEG plasticizer, but I am not being able to optimize the contents.
1. In what quantity range (wt% or vol%) should I use alumina to get high relative density?
2. In what range (wt% or vol% w.r.t total composition or w.r.t alumina) should I use PVA binder? Should the PVA added be in solid granules form or aqueous solution, and hence will that quantity represent binder active matter or binder solution?
3. Should PEG added be in aqueous solution form?
4. Is optically high grade PET film ok as substrate for tape casting? Can the tape be detached from this substrate easily? (I could not be able to detach yet).
Thank you so much~
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Hello Khalid,
I have some experience working with aqueous alumina tapes, but instead of PVA and PEG, used an acrylic emulsion that performs both functions (binder and plasticizer).
For this particle size, I sintered tapes with 25 vol% (~52 wt%) at 1550 ºC for 2 h and obtained a relative density higher than 98%.
The solid content will depend on how you performed your slurry optimization (dispersant, binders, etc.). By the correct optimization, you will find the higher solid content and formulation suitable to produce defect-free tapes.
PET film works good as carrier film and should be OK for you to detach the tape. You can use also a silicon-coated PET film that would help you to easily detach the tape. However, in this case, you may need to play with some tricks of the surface stresses between silicon and the ceramic slurry.
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I'm working with a dielectric ceramic material. I plotted tangent loss V's frequency and it doesn't show any peak which corresponds to the relaxation mechanism. What does this mean? How to interpret the data?
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As a first step, use a logarithmic scale for the frequency. While using a linear scale, you loose all the information bellow a certain frequency value (below ca. 200 kHz in your case).
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I am trying to calculate the theoretical density of my ceramics materials. I use the formula below to calculate the theoretical density: Theoretical density = (Molecular weight x No. of molecules per unit cell) / (Volume of unit cell x Avogardo's number). The issue is how to calculate the Z number? I found that the value of Z even changes as the original materials is doped. please see the attached image of PDF infor for LaFeO3 and La0.8Ca0.2FeO3. The value of Z change from 4 to 2. So, my question is how to exactly calculate the Z value? And why does the value of Z change?
I will be very appreciated if someone could help me out.
Thanks in advance!
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Z corresponds to the lowest multiplicity out of all occupied Wyckoff sites in the respective unit cell and is therefore closely related to the space group symmetry as Michael Patrick Mueller mentioned.
In oP20 (or Pnma, spgr #58) four different Wyckoff sites exist: 4a, 4b, 4c, and 8d. Z = 4 because one or more Wyckoff sites with multiplicity 4 are occupied.
In oI10 (or Immm, spgr #71) there are 15 different Wyckoff sites ranging from 2a to 16o. If one of the four Wyckoff sites with the multiplicity 2 is occupied, Z=2.
Please note that this technically also changes the chemical formula from ABX3 to A2BB'X6, where you have two crystallographically different Fe-ions. If you used two different transition metal cations, they would share the 4a site in oP20 in a disordered fashion, but in oI10, those two cations could occupy two different sites with perfect order (see Sr2WFeO6 for example).
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I am conducting research into additive manufacturing metal matrix composites at the university of Wolverhampton (UK) but I am struggling to locate this information. any help would be appreciated. if you have written a paper that includes this information that would be a bonus also.
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The surface of silicon carbide is covered with a film of silicon dioxide in almost all conditions, so you should focus on the surface properties of SiO2 and not on SiC. In the field of semiconductor technology (silicium waver), this issue is well studied.
By the way, the problem with poor wettability of silicon carbide by metal melts (except for melts of active metals: aluminum, magnesium, titanium, silicon, etc. ) is caused precisely by the presence of a SiO2 film on the surface of SiC grains.
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For a PbO-SiO2 glass, PbO is a network modifier for up to 30-40%, but it becomes a network former at higher concentration. Why?
  • Is it related to oxidation state change of Pb, from 2 to 4, and vice-versa? Pb (II) oxide has distorted tetrahedral coordination and Pb(IV) oxide has distorted octahedral coordination.
  • is the bridge-breaking by low PbO content likened with alkaline earth metal ions? Then what mechanism can be attributed to its bridge formation at higher concentration in Pb-silicate glass, and what is the exact nature of coordination change at this stage?
  • If the glass in not simple Pb- silicate, but rather Pb- alkali/alkaline earth(aluminosilicate), than what is the compositional role in this "role-change" of PbO?
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Pb2+ can act as a network former in oxide glasses when its lone electron pair is sterically active such that the Pb2+ ion forms only 3 to 5 short, strong, bonds to oxygen, typically in the hemisphere opposite that occupied by the lone pair.
By the way, I would not say that there is clear evidence for a strong change in behavior of Pb2+ between modifier and former in pure PbO-SiO2 glasses. Such a transition is much more clear in other systems such as PbO-B2O3.
So no, the modifier-former role of Pb is typically not related to oxidation state changes, rather it is the steric activity of the Pb2+ electron lone pair, or similarly the polarization of the Pb2+.
Adding other elements such as alkali to PbO-SiO2 can have a big impact on the role of Pb, because it can encourage formation of more ionic Pb-O bonding (longer weaker bonds) which cause less polarization, and more of a modifying role for Pb2+. This last part is my personal understanding/conjecture.
Please see:
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It's something I've seen as trial and error, but to make it a little more technical I haven't seen a route for this process. Does anyone have ideas for this route?
I'm talking about the case of rotational reometers.
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Dear Juan Fernando Hernandez, what is this unseen before finding? You forgot to mention that. My Regards
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Dear Colleagues,
The term of bending strength and flexural strength are interchangeably used to measure the strength of ceramic materials. I am aware about the bending strength. Ceramic materials are brittle in nature and lack of plasticity. Hence, bending strength is difficult to count preciously in ceramic materials. However, there are numerous papers measured bending strength of several ceramic materials.
Flexural strength is another frequent used strength measurement for ceramics.
1-What are the main differences between these terms?
2- Why these strengths are important to measure separately?
3-are these strengths can be related to other strengths such as compressive strength of ceramics?
4- is there any difference in the relationship of porosity, microstructure features, density and other parameters relation with bending strength and flexural strength separately?
Thank you very much for your kind contribution and assistance.
Yours sincerely,
Zhwan
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I think both are the same. You may know, sometimes the authors have a plagiarism issue during the writing process of their papers. To decrease the similarity index of a written text, we should use different words and synonyms. Such limitations may cause using various terms for one concept.
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Ceramic materials like Chromium oxide and Aluminium oxide have high melting point. The combustion flame can reach up to 3000 centigrade. However, The velocity of particle may not allow ceramic powder to melt completely.
But I want to know can we coat these materials by optimizing process parameters like flow rate of fuel gas, air and powder feeder?
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Many commercially available spray powders of Cr2O3; Al2O3 and ZrO2/Y2O3 are suitable for plasma spraying and not for flame spraying. However, there are also a pair of spray powders that have been optimized for flame spraying. For example, Castolin sells such powders for its flame spray gun DS 8000:
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Essentially every published review paper on the MAX phases includes Sc2InC in its listings of 'known MAX phases'. However, most of these reviews either: 1) specifically do not reference Sc2InC, while all other phases are referenced, or 2) point the reader in the direction of an earlier review paper.
This paper-trail can be tracked back to the seemingly original source - L. E. Toth, W. Jeitschko and C. M. Yen, The superconducting behavior of several complex carbides and nitrides, Journal of the Less-Common Metals, 10 (1966) 29-32. However this source refers only to Sc2InC as a "personal communication" between W. Jeitschko and E. Parthe. As far as I am aware there are no further reports on the physical synthesis of this phase.
Does anybody know if the origins of this phase go back any further, what the personal communication entailed, or if a publication or any other report has in fact been published regarding this phase which has slipped through my review of the literature?
Thank you in advance.
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Thank you for your response!
Yes, I have read the two publications before and they seem to be well aligned with my thoughts that the compound probably has not been successfully synthesized before.
More generally, I was wondering why the compound has somewhat become an accepted member of the MAX phase family, considering the lack of published evidence for its physical existence.
Perhaps we may never know.
All the best,
Peter Richardson
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Hi everyone,
I would like to know that which ceramic material (oxide, carbide, nitride etc.) is non-toxic to humans and possess best Anti-bacterical and Anti-viral properties?
Thank you in advance.
With best regards
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I read once something about Silicont Nitride, also ZnO. If I recorded well, it has something to do with needle like microstructure.
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I am working on ballistic simulation. The first issue is how can i control hourglass for ceramic materials. Because if hourglass exceeded 10% of internal energy, the simulation will be invalid.
Type 4 or Type 6 , which is better for ceramic ?
And the second question ,if sliding energy is negative but still under control , does it matter for simulation results?
Thank you for your attention and look forward for the answers
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Can anyone suggest an "accurate" lab technique for measuring thermal conductivity (TC) of molten nitrate salt-based nanofluids, doped with Al2O3 metal oxide nanoparticles at various volume fractions (ranging between 0.5% to 5%). The main issue here is to measure fluids/salts TC at high temperatures (ranging from 250-500 ºC). Also for this type of testing what would be the best fit for the sensors insulation?
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Dear Bashar,
I think that we can benefit from yourself answering the question after all this time.
You are an expert now.
Regards,
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Can anyone share a complete poling process of pyroelectric ceramic materials including equipment name and source?
I have never done that before but I need to purchase equipment to perform a polling process. After polling, what type of test should I do to see that the polling was successful and what equipment I need?
It will be helpful if anyone can give a list of processes and equipment requirements.
Thanks.
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Hi Rasedul,
You do not actually need a lot of equipment to do the poling process. Here is a list of all that you need (sintered ceramic samples):
1. Spring loaded copper electodes.
2. DC voltage generation setup.
3. Hot plate or any other suitable temperature regulator.
4. Silicon oil.
Coat the working faces of your sample with silver paint. Clamp it between your electrode setup. Immerse the electrodes in silicon oil. Slowly raise the temperature to near reported Curie point. Switch on the DC voltage and ramp it up such that applied electric field across the sample corresponds to the reported saturation polarization values. Keep the voltage applied for a short period of time (usually 30 min). Slowly cool the sample back to room temperature while keeping the electric field steady. Finally, switch off the high voltage.
With respect to the second part of the question. There are a variety of instruments available from Agilent which can directly measure pyroelectric coeffficient. Otherwise, you can also measure the d33 value as all pyroelectric materials are also piezoelectric.
I hope this helps.
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Difference between Pyrolysis, Carbonization, Graphitization in Composites?- Clear and Specific
Don't copy the sentences from internet sources please.
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Carbonization is the conversion of any organic matter into carbon, for many different processes. Pyrolysis is the chemical decomposition of organic matter in the absence of oxygen. And graphitization is the conversion process of carbon into graphite, is mostly used in metallurgy but can be done in other fields
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Dear researchers ;
I find difficulties to calculate the weight contents (mass%) of kaolin, talc, and alumina corresponding to the ratio of MgO:SiO2:Al2O3. Could you help me please ? 
Thanks for any answers !
Best regards
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It's very interesting, Thank you Dr. Ebenezer Jacob Dhas D.S
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To measure flexural strength of CAD CAM ceramic materials,is it necessary to prepare the samples as crowns on prepared teeth or can we just use blocks of predetermined dimensions. There are studies which have used the latter method. I am curious to know if it makes any difference in the results in using the above two methods of preparing the specimens. Kindly suggest.
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Just mentioned in pure materials mechanics, I would like to separate your question into two parts, as below:
1. Flexural strength measure of CAD/CAM ceramic materials
2. Flexural strength measure of CAD/CAM ceramic crowns
The main issue of your question is how to prepare a sample for this test. There are two sample preparation methods, depended on what is your objective, as the answer of Roland Frankenberger.
## For the 1st issue:
If just account on the material thermomechanical properties, please follow the ISO technical guidance ad the used material strength destructive equipment's guidance for sample preparations. There are very different between different standardized material flexural strength measurements, such as three-pointed (3PFSM) or four-pointed flexural strength measurements (4PFSM), for specific equipment and laboratory standards. However, those results just represent for generic flexural strength (material properties) of a specific sampling modulation of studied material only. For example, you can refer to ISO guideline for ceramics, such as ISO 14704:2008, the specimen length is standardized (in mm) as 30 +/- .1 (for 3PFSM tests), or 40 +/- .1 (for 3PFSM tests), at this link: https://www.iso.org/obp/ui/#iso:std:iso:14704:ed-2:v1:en
It is formally used in most of the dental restoration strengths studies.
## For the 2nd issue:
Especially in the case of multi-units, the generic material flexural property test is not meaning intuitively and reasonably in the practical in-vivo studied, due to omitting the effects of chewing behaviour, chemo-biological media, physiological condition of a tooth root stability, restoration shapes (CAD designs), machining effects (CAM/CNC machining of the green states of zirconia or the final state of chair-side CAD/CAM systems), sintering effects (post-machining (sintering) thermal residual stress distribution), and even function-based indication of each prosthodontist. Furthermore, the real restoration structure is more complex than the determined standard material samples, so the property performance is more complicated in reality. For the real/ practical simulation of in-vivo tests or in-silico tests, the crown-shaped samples are recommended, but that is a case-by-case study only.
In my opinion, to measure the realistic dental CAD/CAM ceramic material flexural property, the sample modelling should be categorized into the design-based groups, such as:
1. Group A: Single cuspid crown, if the FSM of cuspids is interested. The simple bicuspid represented sample might be used.
2. Group B: Multi-unit structure, if the FSM if over-structure is interested. The represented samples should be divided into the followed sub-groups:
** Group B.1. three- or four-unit crown bridge structure represented for curved and spanned arches (anterior or lateral/ aside bridges), with constant spanning (having the same length) and uniformed cross-sectional connections (simplest is circular or bottom-up curved triangular) between the adjacent units.
** Group B.2. three- or four-unit crown bridge structure represented for straight and spanned arches (posterior bridges), with constant spanning (having the same length) and uniformed cross-sectional connections (simplest is circular or bottom-up curved triangular) between the adjacent units.
Notes:
1. The constant telescopic and simple abutment-shaped unit design are preferred.
2. In Group B.1. , the samples should be symmetrical, and their curvy ratios are accounted on the ratio of the arch radius to Euclidean length between the ends.
3. Sintering condition should be systematically studied as a key-input for those studies (for the green state CAD/CAM ceramic restorations).
4. No chemo-biological media is applied.
5. If available, the photoelasticity test could be more intuitive for this test.
Hope that could be helpful for you.
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Dears, I am looking for an efficient software (preferably free) to carefully analysis the porosity, phase composition percentage , clearly distinguish between phases, grain size for EACH ELEMENT, grain size distribution and other parameters related to the microstructure analysis to related them to hardness, fracture toughness and strength of advanced ceramics materials? Thank you very much for your kind cooperation in advance. Yours sincerely, Zhwan
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ImageJ/ Fiji is one of the most popular software for analyzing gran size, weight percent, distinguish of each phase and so many other benefits. For estimating mechanical properties like hardness, strength, and fracture toughness utilizing simulation software like Jmat Pro can be a great help. Hope these informations solve your problem.
cheers,
Nemat.
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In my case, after successive doping in my sample (bulk), one of the peaks starts splitting into two. what could be the reason behind this?
Is this caused by strain in structure ?
plz give answer with reference...
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Before being able to answer your question, we'll need to know a few things:
  • Does black = undoped and purple = doped?
  • Does purple = partial substitution?
  • Is the dopant heavier than the atom/ion that used to sit at that site?
  • Does the frequency increase as you move to the right along the x-axis?
If so, then I think that both peaks correspond to the same vibrational mode. The peak on the right corresponds to the vibration including the original, lighter atom/ion and the peak on the left corresponds to the vibration including the heavier dopant. You can understand this intuitively using a simple model of two masses (m1 and m2) connected by a spring with a force constant k. The stretching frequency for this system is given by
f = sqrt(k / u)
where
u = (m1 * m2) / (m1 + m2)
If you increase one of the masses (analogous to doping), then u increases and f decreases. This could explain your result but only if you can answer "yes" to those four questions above.
Please let me know if you have any further questions.
Best,
Rob
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I calculated activation energies for intermediate stage of sintering for alumina+tetragonal zirconia composite and alumina+cubic zirconia composite via non-isothermal CHR method in microwave hybrid sintering, and compared them. The particle sizes of both as-received zirconia were same. A+tZ shows slightly higher activation energy as compared to A+cZ, but the densification of A+tZ is also higher. Can someone please guide? Because if densification is higher, then the activation energy for sintering should be lower, but that's not the case here. Is some unusual factor of sintering kinetics involved here?
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Activation energy for a sintering is a system property, namely: the energy barrier which system must overcome to start sintering process. In the discussed case, obviously, the estimated activation energy is a combination of surface/grain boundaries/volume diffusion activation energies of the mentioned materials system.
On the other hand, densification is a sintering result. So, is sintering parameters permitted to overcome the energetic barrier, a sintering process was initiated and then resulted in a certain final density.
Taken into account the mentioned above, I do not see any contradiction between high activation energy and high sintered density, if sintering process was adjusted and optimized specially to the mentioned materials system.
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May you know any methods/software/ or techniques capable of refining a series of similar XRD patterns? I am talking about Rietveld refinement.
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You should try GSAS and FullProf, which are highly respected free packages...
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1. Proper surface finish 
2. Better bonding of ceramics with adhesives
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Thank you Mr.Melentiev. I'll try your suggestion.
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Respected Sir,
As we know, the ceramics are brittle in nature, if we add polymer and ceramics in piezo ceramics, then the material behaves as flexible. What is the main reason behind it?
Kindly share your valuable answers,
Thanks and best regards.
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Polymer is itself flexible material. By adding polymer to ceramics, definitely it will become flexible instead of brittle. It depends on how much polymer used in the ceramics. Also depends on the different applications of the ceramics.
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Please list down the best best Scientists/Researcher in the field of Solid State Electrolyte/Solid-state batteries for Li/Na-ion batteries.
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Hi
you can check those:
Prof. John R. Owen
Prof. Peter Bruce
Prof. B. Scrosati's
Prof. Linda F. Nazar
Prof. Jean-marie tarascon
Prof. Doron Aurbach
Prof. Hubert A. Gasteiger
Prof. Arumugam Manthiram
Prof. Yi Cui
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For refractory brick we measure the refractoriness with Orton cone (standard cone)
What should be the PCE value (theoritical) for the refractory having following chemical analysis.
Al2O3 : 74%
Fe2O3 : 0.6%
SiO2: 24%
Na2O + K2O : 0.25%
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I am assuming that the composition that you specified is in mass %, and NOT mole %. Converted to mole % for the Al2O3-SiO2 binary system the composition is about 63.87% Al2O3 and 36.13% SiO2. You can use that to read off the binary diagram that you can find here:
The system is fully solid at 1800 C, and fully liquid at 1900 C. You can use FactSage (www.factsage.com) to get more detailed information that incorporates Fe2O3, K2O, and Na2O.
The stability of the material as a function of temperature is just one consideration. The material that you will contain with the refractory material is just as important, since it can flux the refractory and create a low melting point composition.
All the best
Johan
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In my ceramic sample which is highly fragile and porous, structure is destroyed on doing FESEM during placing on the stab holder, even charging of the sample take place even at low magnification.
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Try to sputter a thin gold layer to avoid charging and possible this layer will give you some hardness of the investigated material.
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Why we don't put the rogowoski current sensor in a metallic enclosure? Because for a metallic case (grounded), the sheath thickness will be small as compared to a floating ceramic enclosure.
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I think, its better to think it another way round. What happen when the metal face a plasma?
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I am need of a good electrical insulator, which can resist temperature up to around 1200-1400 degree centigrade.
I know Teflon (Polytetrafluoroethylene (PTFE)) which has a melting point of 327 degree C.
Actually I need a insulator which can resist high temperature, it should be electrical insulator and moreover should have adhesive property like that of araldite.
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machinable ceramics h-BN and SiAlON-BN are highly recommended
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How to convert the fracture toughness to strength?
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Andrey:
Dr. Kern is absolutely correct. Any relationship between strength and fracture toughness would have to be for brittle materials as both material properties depend on the presence of cracks and on fracture. However, that's where the connection ends as the strength of a brittle material will be dependent on the bond strength and importantly the distribution of defects (and their size) that are present invariably in a macroscopic (tensile or bend) specimen (note here that brittle materials such as ceramics are weaker in larger test samples as there is a higher statistical probability of find a larger flaw. In contrast, to measure the toughness, e.g., KIc, you will have inserted a worst-case starter crack in your sample and so the distribution of inherent cracks in the material is less important; moreover, the active volume of material engaged in the fracture, i.e., within the crack-tip process zone, will be orders and orders of magnitude smaller than in your tensile or bend specimen used to measure strength.
For a ductile material, on the other hand, all bets are off! There can be no scientifically viable way, in my opinion, of ever converting fracture toughness to strength as they assess completely different properties of a material. Toughness is resistance to fracture, strength in ductile materials is resistance to plastic deformation. Indeed, they are effectively mutually incompatible properties. If you are interested, I have written a short paper on this which is attached.
ROR
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For a tetragonal zirconia, is it 210 GPa?
And for cubic?
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Hi, Andrey Leonov
Your value 210 GPa of Young's modulus of tetragonal zirconia was in the range,and its about 222 GPa for cubic zirconia.
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When indented by a Vickers diamond pyramid, a crack is formed as shown in the figure. What is the distance from the corner need to measure, 1 or 2?
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Generally, the half of crack length should be measured from the center of indentation. Please see the attached figure.
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We use Vickers indentation method for estimation of the fracture toughness. We use the following formula, Fig. 1. The calculation requires the average length of cracks. If there is only one 8 μm crack (Fig. 2), then we take the average 8 μm? Or (8+0+0+0)/4 = 2 μm?
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I think the load of indentation, you have used, was not high enough to induce the radial cracks at all corners of indenter's impression. I recommend you to increase the load and repeat the test for 3 or 4 times. In my opinion, you can not rely on only one indentation as well as on the length of only one crack instead of four cracks.
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As, Titanium Nitride has a complex structure and it is also transition metal nitride, literature says it is a ceramic material but it still has high electrical conductivity like metals.... Why is that?
and also can you please help me in helping precisely finding the band gap of TiN? Does it have a band gap as it behaves like metal?
Thank you
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The direct optical band gap of Titanium nitride thin films is close to 3.62 eV. The allowed energy band gap of the films can be determined by applying the optical transmission spectra over a range of 200–1100 nm using the Tauc’s relationship for the absorption coefficient, α in equation below ahʋ = Ai(hʋ-Eg)m, where A is constant and has different values for different transitions, Eg is the energy gap, hv is the photon energy and m is an exponential constant which assume the values 2, ½, 3/2 and 3 depends on the optical electronic transition.
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Ceramic coating is provided on the metal to improve its wear resistance. There are many ceramic materials are available and seems not easy to choose best one which can fulfill our requirement. What criteria should we use to select the best material?
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In real machines, materials are almost always exposed to the complex effects of various factors. For example, abrasive wear in combination with wet corrosion; variable mechanical loads in combination with dry friction or contact friction plus thermal shock combined with oxidation at high temperature. There can be a lot of such variations and they all require different properties from coatings.
For the above reason, it is simply not possible for a single coating to meet all the requirements at the same time.
For example, WC-Co and WC-Co-Cr coatings are characterized by very high resistance to abrasive wear and wear in friction pairs, but are unsuitable for operation at elevated temperatures and under conditions of high variable mechanical loads on the substrate. In turn, Cr3C2-NiCr coatings are cheaper and better than WC-Co coatings withstand elevated temperatures, but are less resistant to wet corrosion and have higher friction coefficients in friction pairs. Hard chromium coatings are cheap, suitable for application to complex surfaces, but have relatively weak mechanical properties and low corrosion resistance due to the grid of microcracks.
In general, it is much more difficult to find a coating resistant to high temperatures and various types of corrosion than coatings resistant only against abrasive wear (I am just working on such corrosion-resistant coatings).
By the way, very often clients incorrectly estimate the load on coatings and choose coatings that are unsuitable for their specific tasks.
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This question is to those who are experts in metals and metallic coatings.
For a particular application, I have to add very small quantities(ppm/micro gram level) of an inorganic ceramic material into metallic parts (steel,brass etc.) during their formation.Is this possible?If not, any other way to mix the ceramic particles with something and give a permanent layer coating outside?Like thermal spray or galvanization.
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There are an infinite number of such combinations under a common term "cermets". Also, methods for making cermets are very numerous, as well as for compact materials, as for coatings. Cermets can be produced in normal metallurgical processes (melting + casting), but much more possibilities are offered by powder metallurgy (powder compaction + sintering).
Strictly speaking, many well-known hardened metallic materials are exactly the cermets you are looking for - very fine hard ceramic particles strengthen the soft metallic matrix! Carbide (iron carbide, chromium carbide, vanadium carbide and others), but also intermetallic hard compounds (NiAl, NiTi and others) and oxide phases (SiO2, Al2O3, Y2O3 and others) are found in many metallic materials.
Combinations of glass and metal are also possible and used, for example photo glasses with nano silver particles and glass-ceramics with various other metallic particles.
The cermet coatings can be made by thermal spraying, cladding, pvd/cvd and electroplating.
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While fitting Cole-Cole plot to equivalent circuit model using C, R, Q; different circuit models are changing with different temperature range. The sample has grains and grain-boundaries
C= capacitor
R= Resister
Q= constant phase element.
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Dear Sirs
The approach to find a specific model for each temp is called spot model approach and its acceptable for simulation packages. As an example for more clarification , for device models that work in a certain frequency range (2-12 Ghz), you can find easily a device circuit model for each frequency spot (2,4,6,8,10,12 Ghz) that simplifies the simulation purposes.
Good Luck.
Prof. S. EL-Rabaie
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Actually I was working on a piezoelectric project and I kept the 99.9% pure bismuth oxide powder at 800 C for 4 hours. When I opened the furnace, the bismuth oxide got sintered and took the form of the crucible. I almost placed 100 g of Bi2O3 in the furnace and now the weight of the solid sintered product is roughly the same. I would like to know if there is any way by which I could recover the powdered Bi2O3 without contaminating it?
I could make almost 10 batches with this amount so I don't want to discard it.
P.s. I have planetary ball mill (with Zr medium) and mortar and pestle.
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Thank you for your responses. I first ground it using mortar and pestle then did ball milling for 2 hours. I got my powder back. Now I will do XRD to confirm if it's actually Bi2O3 or not.
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I need your help to obtain thermal stress in a ceramic material.
I usually work with metalic materials but in this case I need to develop an analysis using a ceramic material under temprature changes.
I want to know how to define a ceramic material in Abaqus.
Regards.
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A ceramic material is in general brittle elastic. There may be symmetries in the material, although that depends on the specific case. Thus, for mechanical properties, you'll need only the elastic ones (keyword *ELASTIC). Then, as you're studying thermal effects, you're going to need some thermal properties. If you are interested only in thermo-mechanics, the only properties you need to add are thermal expansion coefficients (I used the plural as their number depends on material's symmetries), i.e. keyword *EXPANSION. If you are instead going to study transient thermal effects, you'll need also thermal conduction coefficients ( *CONDUCTIVITY ) and specific heat of the material (*SPECIFIC HEAT). In more advanced cases, you can add a damage behavior to the material.
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Which approach is more recommended, thermal or chemical? If later, what chemicals are effective?
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Hi Michal,
If you are looking for etching technologies for SEM you have to consider the type of SEM you have. These zirconates are typically relatively coarse with grain sizes > 1 micron. If you have a conventional SEM I would recommend etching at 1250-1350°C for 10 min in air, do not go higher than 10-15 kV. If you have an in lens SEM with higher resolution etch at 1150-1200°C for 5 min, stay below 5-10 kV.
You may have to play around with the etching parameters if the result is not perfect. Better use PtRh or Ir than Gold.
best regards
Frank
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I have measured total conductivity (electrical + ionic) of a ceria-based oxide by impedance analyzer in two ways:
1. By keeping the temperature constant at a time (like 400, 500, 600 700 °C etc.) and changed the frequency from 1 KHz to 10 MHz
2. By keeping the frequency constant at a time (like 1, 10, 100, 500, 1000 KHz etc.) and changed the temperature from 300 to1000 °C.
Is total conductivity measured by both methods would be similar for the data taken at the same frequency and temperature (for example at a frequency of 10 MHz and temperature of 1000 °C) or it would be different? Please explain.
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Imad is right, however, we should think what could happen within the defined parameter field. Change of frequency will probably be harmless. Ceria is prone to reduction at high temperature due to thermodynamic boundary conditions. So if at high temperature some reduction takes place and the numer of oxygen vacancies are increased, this would affect subsequent measurements at lower temperature as under this conditions re-oxidation would be extremely slow. To be sure that the sample history does not interfere with the measurement better use a fresh sample for each measurement.
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The production of components and assemblies in the nuclear area employs fusion welding and in the solid state as a method of manufacture in the various metallic materials. With the increasing use of new ceramic polymer materials and composites new bonding techniques need to be developed.
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Dear Colleagues,
Many thanks for all the answers.
SP
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I want to increase ionic conductivity of oxygen ions in a ceramic disk made by powder metallurgy route. Which materials can be added in the ceramic powder and in what % that can increase ionic conductivity of O+ ions. Your valuable suggestions are invited. Thanks in advance.
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Hi Satish,
From technically relevant ceramics, only ceramics based on ZrO2 conduct O-2 ions (by the temperature > 750°C). The denser this ceramic, the better conductive it is. Since no ceramic can be made from pure ZrO2, it is about compositions ZrO2 + stabilizer (CaO, MgO or Y2O3). The best variant for a conductive ceramic is one with 7-9 mol-% Y2O3 stabilized ZrO2, short name: YSZ.
Regards
Vadim
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Currently we are mixing fiber in water but the fiber are getting coagulated and are forming small chunks as shown in picture 1 and picture 3. The fiber is not completely dispersed. What should be done to form a uniform dispersed slurry of the fiber without forming chunks?
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Try lowering the pH with acid, to see whether increasing the surface charge helps.
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Researchers working on Materials Science 
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Yes for sure above ceramic solutions are of high interest but I think PVDF is a very good alternative with its low stiffness and high electromechanical coupling coef. PVDF could also be processed at larger scale (especially high surface transducers). regards
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I'm using GULP to test an interatomic potential for a ceramic material. I'm interested in describing how the volume of the unit cell changes with temperature. I've used GULP to minimize de Free-energy of the system at different temperatures and I can find a reasonable change in the volume. However, when using a NPT molecular dynamics using stochastic integration of the equations of motion the system reaches equilibrium at a smaller volume. Is this a common phenomenon in MD?
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If GULP explicitly considers the Einstein/Debye density of states at low temperatures, which deviates from a simple Boltzmann distribution achieved in MD, then of course, that could cause deviations. But this would only be visible near 0 K. Is that the temperature you're using?
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I am trying to exfoliate Ti3AlC2 with the method of Li/HCl. Ti3AlC2 (>=98%) was purchased, and has been characterized by XRD. Since the HCl itself is not enough to exfoliate Ti3AlC2, i added 12M HCl to Ti3AlC2 directly, and stirred for several hours. For a couple of hours, even half of the day, nothing happend, Ti3AlC2 in the solution just sank, and the supernatant was clear. However, after maybe 2 days(start from the moment i mixed them), i caught sight of the solution, it has turned to pink(i am not sure about the exactly color, a little bit purple or red ?), and the supernatant was still clear. Next, i collected some to do UV-Vis, results hasn't come out yet. Is there anyone know what such solution is? Ti2CTx (T=OH, F, O) ? If so, can i make a conclusion that i can wash the Ti3AlC2(remove the impurities) in this way?
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(Not my expertise, so wait for others...)
BUT - a simple wiki look shows that titanium ions (Titanium3+) are violet? this would give you a pinky-purple shade if you've got Ti3+ in solution?
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i have prepared calcium phosphate ceramic material, which contain both nano(below 1 micron)and micron(5-10micron) size particles. but i need only micron size particles, how to separate micronsize particles?. i tried to use 5 micron seive but still smaller particles are present in my ceramic material.
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Dear Anbuthangam,
There is no industrial method to completely separate particles smaller than 1 microns from particles of 1 to 5 microns. Sieving does not work with such particles (small mesh size for industrial applications is 20 microns). Air centrifugal classifier also can not separate such fractions.
Only thing you can do - continue grinding the whole powder. With proper wet milling (small grinding ball, long time) you grind all your particles in the submicron size.
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Hi Dr. :
I am Ph.D and investigate the high impact of ceramic composite plates.
I have several problems in LS-DYNA and must consult with you.
I study high velocity impact with Al2O3/6061-T6 Al composite plate which ceramics use MAT_110 JH-2 model of ANSYS/LS-DYNA software.
The thickness of ceramics was 11 mm and Al was 1mm by using 0.30 AP bullet.
I had once changed the value of A B C M N T FS HEL PHEL D1 D2 K1 K2 K3…etc in LS-DYNA, but the residual velocity didn't always decrease, the initial velocity was 868 m/s, the residual velocity was approximately 700 m/s.
And how does the ceramic model simulate the crack phenomenon ?
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hello I'm doing similar work on ballistic impacts on ceramics with LsDyna.
Although I''m not getting comminuted fracture of ceramic. I'm using hard steel core projectile. Please help me in modeling the ceramic materials.
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I am using ceramic membranes of 100 and 200 nm pore size for separation of oil from produced water of 500 ppm oil. There are many methods in literature. I want the simplest method using NaOH solution.
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Cleaning Procedure
1. Wash membrane with a 15-20g/L alkaline cleaning solution of sodium hydroxide (NaOH) at a temperature of 85° C
for 30 minutes.
2. Rinse membrane with water until pH returns to neutral.
3. For MF-UF membranes, wash membrane with a 5ml/L acid solution of nitric acid (HNO3) or solution of 75%
phosphoric acid (H3PO4) at a temperature of 50° C for 15 min. For NF membranes, wash with a 1ml/L acid solution of
75% phosphoric acid (H3PO4) at a temperature of 50° C for 15 min.
4. Rinse membrane
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Lanthanum modification at the A-site for PbZrTiO3 shows decrease in grain size and transition temperature
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The reduction in grain size with the addition of La could be attributed to the impurity drag mechanism in solid solution in which the La ions gradient is present at the grain boundaries. Another reason for the decrease in grain size is that the addition of La might have restricted the grain growth by resisting the mobility of the grain boundary.
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plz send me some reference papers also.
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Fracture toughness is one of most important mechanical property for ceramic materials. What's the major different between normal toughness and fracture toughness? And how to conduct fracture toughness testing?
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Dr. Hu:
There is really no intrinsic difference between the terms "toughness" and "fracture toughness", other than the former is a generic term and the latter refers generally to the measurement of toughness using fracture mechanics methodologies.
Accordingly, whereas "toughness" refers to any method of assessing the stress, strain or energy to cause fracture, such as the area under the stress-strain curve, the Charpy V-notch energy which is the energy to break a V-notched specimen in three-point bending under impact, or the critical value of the stress intensity K or strain energy release rate G at fracture, the "fracture toughness" specifically refers to the latter two terms, which rely on the measurement of the conditions to cause fracture in the inevitable presence of a defect, i.e., a crack. This is the basis of fracture mechanics - fracture in the presence of defects - and the term "fracture toughness", as opposed to "toughness" specifically refers to the conditions, i.e., stress intensity or energy, for fracture in the presence of such defects!
For this reason, the fracture toughness provides both a reliable measurement of the toughness of a material, but which most importantly,
can be used predictably in design to assess the conditions for failure in a real structure.
ROR
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I have 25mm thickness ceramic based micron size particle material. Apart from I want to do correct reconstruction of the material from X-Ray Computerized Tomography Microscope(XT-400). which one is standard procedure to monitor? Give me the suggestions please?
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Please use the built-in software for reconstruction. It should be optimized for your CT system.
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This is for a ceramic material. Relaxation time should be calculated from this.
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Would you mined if you mention to your available parameters?
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As a kind of ceramic materials, alumina (Al2O3) is really hard to etch. Many thanks to those who can show me detailed info. of etching alumina.
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Hi Yingbin
The best method to etch  alumina (Al2O3) is by a standard procedure of electrochemical etching in order to reveal the microstructure characterization of the sample.
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We are planning to work on modeling of advanced ceramic materials (Thin Solid Films) for energy related applications. What is your suggestion about suitable software for starting up ?
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for MD I would suggest using LAMMPS because of its flexibility
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ceramic material
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thanks sir for your suggestion. 
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