MUSTAFA SAFA YILMAZ

• Doctor of Engineering
• Professor (Assistant) at Bursa Uludağ Üniversitesi

One of the most popular methods of manufacturing metal parts is selective laser melting (SLM). This study uses a novel hybrid manufacturing method for lattice structures, integrating vibration modal and Charpy impact analyses. This integrated approach offers a promising route for advancing the understanding and optimisation of lattice structures in...

In this study, alternative solution heat treatments, applied at lower temperatures and shorter times, were applied to AlSI10Mg samples produced with the powder bed laser fusion technique. Thermocalc software was used to determine the temperatures of the NT6 solution heat treatment. The samples were analyzed by optical microscope, scanning electron...

Powder metallurgy and selective laser melting (SLM) methods are widely used in producing metal parts. Adding reinforcements can improve the mechanical and physical properties of the parts. This study uses the powder metallurgy method before SLM to investigate the effect of copper reinforcement (0, 0.5, 1, 2, and 5 wt.%) on 316L and MS1 (maraging st...

Additive manufacturing systems, which have strict control processes before and after manufacturing, are used in many industries. The quality of the machine’s equipment and raw materials used directly affect the production parts characteristics and quality. Additive manufacturing parts, which give properties close to traditional production methods,...

Additive manufacturing is the production process in which a 3D CAD model is combined into layers, and the material is turned into a physical part. Additive manufacturing is an important technology that is very popular and expected to take a more important place in our future lives. Additive manufacturing is a revolutionary method in automotive, avi...

As with all additive manufacturing processes, selecting appropriate process parameters in the laser powder bed fusion (LPBF) process plays an important role in the surface integrity and mechanical behavior of Inconel 718 components. Hatch distance, laser power, laser scanning speed and layer thickness are the main parameters that can be altered in...

Laser powder bed fusion (LPBF) is becoming more popular and widely acceptable class of the additive manufacturing processes for metallic objects. The impact of test temperatures, sliding speed, and loading conditions on the wear behavior of LPBF generated 316L stainless steel is investigated in this work. The findings revealed that the effect of al...

Additive Manufacturing (AM) has been developing with increasing interest in recent years. The development in this technology will accelerate with the increase in material, process, and product quality. It is therefore essential to investigate these shortcomings of additive manufacturing products. In this study, the microstructure and corrosion prop...

The Additive Manufacturing (AM) process provides opportunities to fabricate products with complex geometries including conformal cooling channels, etc. While having such an advantage, the low surface quality of the products is a disadvantage of laser powder bed fusion (LPBF). Because of that, a post-process is needed to improve the surface quality....

Purpose The present paper aims to systematically investigate the influence of building orientations (0°, 15°, 30°, 45°, 60°, 75°) and heat treatment processes on the macro-/micro-structural, mechanical and electrochemical behaviors of selective laser melting (SLM) prepared AlSi10Mg alloy parts. Design/methodology/approach AlSi10Mg samples were prod...

This study applied classical and intercritical heat treatments to maraging steel (MS1) samples produced with standard additive manufacturing (AM) production parameters. The effects of heat treatment parameters on the microstructure-phase changes of the material were investigated by optical microscope (OM), scanning electron microscope (SEM), Electr...

The unique additive manufacturing (AM) attributes such as tool-less design, on-site fabrication, short production cycle, and complex structures fabrication can make AM market penetration deeper. The sustained improvements in AM's computational hardware and software, advanced automation, affordable equipment, and process, structural, and metallurgic...

Existing studies suggest that martensite-to-austenite reversion can increase the overall mechanical strength of maraging steel. Their effect on corrosion properties, however, is unclear. Selective laser melted (SLM) specimens were tempered near austenite finish temperatures to investigate the electrochemical effect of reversed austenite. X-ray diff...

Additive Manufacturing (AM) technology produces parts in layers and offers design freedom (3D design), zero waste, reduced expensive tool material requirements, and improved mechanical properties. Maraging steels have superior strength and toughness with adequate ductility. The effect of aging process parameters on the final properties of AM Maragi...

In this paper, retrogression and re-aging (RRA) heat treatment was applied to 7075 aluminum alloy in T6 condition at different times (30 and 90[Formula: see text]min) and temperatures (180 ∘ C and 240 ∘ C). While RRA heat treatments increase the corrosion resistance of the material, it does not harm its mechanical properties. On the other hand, the...

Purpose This paper aims to investigate the effects of various heat treatments on microstructure, hardness, porosity and corrosion properties of the parts. Design/methodology/approach Hot isostatic pressing (HIP) process, various heat treatments and their combinations were applied to the AlSi10Mg parts produced by direct laser metal sintering (DMLS...

Micro arc oxidation coatings were produced on AA7075 (UNS A97075) substrates using various process parameters. The study aimed to improve the surface characteristics of the alloy. Thickness, hardness, and roughness measurements characterized the coatings. It was revealed that the coating thickness was directly related to the coating roughness. Vari...

Purpose The purpose of this paper is to evaluate the effect of post process combinations, e.g. hot isostatic pressing (HIP) only, HIP + T6 heat treatments, and T6 only, with different aging time, on surface properties, microstructure and mechanical properties of stress-relieved AlSi10Mg parts produced by direct laser metal sintering. Design/method...

In this study, Polymer (Primecast® 101-EOS)patterns were produced with the EOS Formiga P110 system, and these patterns were compared with conventional wax patterns using their suitability for the investment casting (IC) method. Besides, Scanning Electron Microscope (SEM) and Thermal Analysis (DSC and TGA) were applied produced to investigate the pr...

In this work, hot isostatic pressing and subsequent T6 heat treatment, by using two different aging durations (4h and 12h), were applied to laser sintered AlSi10Mg materials to evaluate the effects of secondary process combinations on properties of DMLS AlSi10Mg alloy. Relative densities and open porosities were determined using Archimedes method....

The aim of this research is to reach a deep understanding on the effect of the process parameters of Direct Metal Laser Sintering process (DMLS) on thermal and mechanical properties (thermal conductivity, porosity and compression) of AlSi10Mg parts and resulting microstructure. In this study, a variation of the thermal, porosity and mechanical prop...

In this study, AlSi10Mg samples produced by the direct metal laser sintering (DMLS) method were applied to heat treatment with different parameters (stress relief and T6). Heat‐treated and as‐built samples were subjected to intergranular corrosion test according to BS EN ISO 11846 standard. Hardness, tensile, electrical conductivity, scanning elect...

The present study is an investigation of the effect of pulse duration on properties of coatings formed on aluminium alloy in alkaline solution via using of high voltage cathodic pulses. Nine different anodic-cathodic pulse couples with various durations were selected for processing. In order to find out the effect of pulse duration on coating: duty...

Aluminum and its alloys are fundamental to several industries. Micro Arc Oxidation (MAO), is a technique which was developed to improve the qualities of Aluminum and its alloys. MAO produces thick and hard alumina coatings which have a combination of wear resistant, thermal resistant and corrosion resistant properties. The aim of this study was to...

Electro-Spark Deposition (ESD) technique is used to improve mechanical properties and corrosion resistance of metal surfaces. In the present study, steel surfaces that were coated with zirconium electrode materials by using ESD technique have been characterized. Firstly, the electrical parameters of process were investigated to achieve a best coati...

Micro arc oxidation (MAO) of aluminum alloy samples was studied using bipolar pulses with various pulse durations under constant duty cycle. The processing times were chosen as 20, 30 and 40 minutes. The X-ray diffraction (XRD) technique, scanning electron microscope (SEM), surface roughness measurement (Ra) and in- dentation tests were employed to...

In this study, micro alloy steel (St 35) surfaces, which were coated with different hard alloy electrode materials via Electro Spark Deposition (ESD) method, have been characterized. The electrode materials were chosen among hard alloys such as; TiCN(Ni), CrC-NiCr, WC(Co) and TiWC(Co). During the ESD experiments, the following pulse parameters in a...

In the present study, first Ti6A14V alloy was deposited on steel (AISI 1060) surfaces by using ESD method. The optimum electrical parameters for the coating process were investigated to obtain high quality coatings. Then, in order to gain bio-compatibility and obtain second layer, which was coated with hydroxyapatite (HAp), MAO technique was applie...

Al-Ti intermetallic compounds were coated by electro-spark deposition. Commercially pure titanium (Cp-Ti) (grade 2) and aluminum rods were used as substrate and electrode materials, respectively. During the electro-spark deposition experiments the following pulse parameters in a group were used: pulse current amplitude, pulse duration and pause bet...