The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
Tahir I. Khan - One of the best experts on this subject based on the ideXlab platform.
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the effect of Quenching Medium on the wear behaviour of a ti 6al 4v alloy
Journal of Materials Science, 2008Co-Authors: C. Feng, Tahir I. KhanAbstract:The aerospace alloy, Ti–6Al–4V is a difficult material to machine, and, in general, shows poor wear resistance due to the soft, ductile properties of the alloy. In this study, the Ti–6Al–4V alloy has been heat treated to a temperature above and below the β-transus temperature and then quenched using a Medium of oil, water or liquid nitrogen to change the surface wear behaviour of the alloy. The results showed that no significant change in microstructure and surface properties was achieved when the alloy was heated to 750 °C and then quenched in liquid nitrogen. However, when the alloy was heated to 1,000 °C (above the β-transus), the hardness of the titanium alloy significantly increased from 400 VHN to about 800 VHN, but the wear resistance of the alloy did not improve. In fact, the wear resistance of the alloy decreased as the surface hardness increased, and this change in wear behaviour was attributed to a change in the mechanism of wear from plastic deformation to brittle-fracture of the surface.
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The effect of Quenching Medium on the wear behaviour of a Ti–6Al–4V alloy
Journal of Materials Science, 2007Co-Authors: C. Feng, Tahir I. KhanAbstract:The aerospace alloy, Ti–6Al–4V is a difficult material to machine, and, in general, shows poor wear resistance due to the soft, ductile properties of the alloy. In this study, the Ti–6Al–4V alloy has been heat treated to a temperature above and below the β-transus temperature and then quenched using a Medium of oil, water or liquid nitrogen to change the surface wear behaviour of the alloy. The results showed that no significant change in microstructure and surface properties was achieved when the alloy was heated to 750 °C and then quenched in liquid nitrogen. However, when the alloy was heated to 1,000 °C (above the β-transus), the hardness of the titanium alloy significantly increased from 400 VHN to about 800 VHN, but the wear resistance of the alloy did not improve. In fact, the wear resistance of the alloy decreased as the surface hardness increased, and this change in wear behaviour was attributed to a change in the mechanism of wear from plastic deformation to brittle-fracture of the surface.
C. Feng - One of the best experts on this subject based on the ideXlab platform.
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the effect of Quenching Medium on the wear behaviour of a ti 6al 4v alloy
Journal of Materials Science, 2008Co-Authors: C. Feng, Tahir I. KhanAbstract:The aerospace alloy, Ti–6Al–4V is a difficult material to machine, and, in general, shows poor wear resistance due to the soft, ductile properties of the alloy. In this study, the Ti–6Al–4V alloy has been heat treated to a temperature above and below the β-transus temperature and then quenched using a Medium of oil, water or liquid nitrogen to change the surface wear behaviour of the alloy. The results showed that no significant change in microstructure and surface properties was achieved when the alloy was heated to 750 °C and then quenched in liquid nitrogen. However, when the alloy was heated to 1,000 °C (above the β-transus), the hardness of the titanium alloy significantly increased from 400 VHN to about 800 VHN, but the wear resistance of the alloy did not improve. In fact, the wear resistance of the alloy decreased as the surface hardness increased, and this change in wear behaviour was attributed to a change in the mechanism of wear from plastic deformation to brittle-fracture of the surface.
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The effect of Quenching Medium on the wear behaviour of a Ti–6Al–4V alloy
Journal of Materials Science, 2007Co-Authors: C. Feng, Tahir I. KhanAbstract:The aerospace alloy, Ti–6Al–4V is a difficult material to machine, and, in general, shows poor wear resistance due to the soft, ductile properties of the alloy. In this study, the Ti–6Al–4V alloy has been heat treated to a temperature above and below the β-transus temperature and then quenched using a Medium of oil, water or liquid nitrogen to change the surface wear behaviour of the alloy. The results showed that no significant change in microstructure and surface properties was achieved when the alloy was heated to 750 °C and then quenched in liquid nitrogen. However, when the alloy was heated to 1,000 °C (above the β-transus), the hardness of the titanium alloy significantly increased from 400 VHN to about 800 VHN, but the wear resistance of the alloy did not improve. In fact, the wear resistance of the alloy decreased as the surface hardness increased, and this change in wear behaviour was attributed to a change in the mechanism of wear from plastic deformation to brittle-fracture of the surface.
Seyyed Mahdi Abbasi - One of the best experts on this subject based on the ideXlab platform.
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Effects of annealing temperature and Quenching Medium on microstructure, mechanical properties as well as fatigue behavior of Ti-6Al-4V alloy
Materials Science and Engineering: A, 2017Co-Authors: Navid Davari, Atefe Rostami, Seyyed Mahdi AbbasiAbstract:Abstract In this research, the effects of annealing temperature and Quenching Medium on microstructure, mechanical properties as well as high cycle and low cycle fatigue behavior of Ti-6Al-4V were investigated. Four types of different heat treatments consisting annealing at 930°C and 970 °C followed by air cooling or water Quenching were considered. Microstructural and mechanical evolutions were evaluated using optical microscope (OM), hardness and tensile tests. According to S-N curves, fatigue behavior followed up the same trend in both high and low cycle fatigue regimes in a way that the higher the annealing temperature and more intense the Quenching Medium, the better fatigue resistance. SEM fractography of fatigue surfaces indicated cleavage ductile fracture mode in all kinds of applied heat treatments.
Olaf Kessler - One of the best experts on this subject based on the ideXlab platform.
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Fine Surface Structures Influencing on Liquid Quenching
HTM Journal of Heat Treatment and Materials, 2020Co-Authors: R. Steuer, Nikolay Kozlov, Olaf KesslerAbstract:Abstract Instead of Quenching Medium, Quenching equipment and Quenching parameters, an adapted surface structure of the heat treated component shall be investigated as influencing factor on rewetti...
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Influencing on liquid Quenching by surface structuring
International Journal of Thermal Sciences, 2016Co-Authors: Nikolay Kozlov, Olaf KesslerAbstract:Abstract Quenching is an important process in the heat treatment of metallic components. This is usually performed as immersion Quenching in vaporizing liquids, such as water. Quenching in water is characterized by relatively small effort and high average Quenching rate. Disadvantage of this method is the occurrence of the Leidenfrost effect. The Leidenfrost effect manifests itself in the fact that a thin vapour film is formed on the hot component surface, which greatly reduces the heat flow between the component and the Quenching Medium. Depending on the component geometry and Quenching conditions the vapour film collapses at different time and location. This causes component distortion and residual stresses. Many studies on the Leidenfrost effect are dealing with influences of Quenching Medium and Quenching conditions. In this work, the influence of component surface structure on the Quenching kinetic has been investigated as a novel approach. The focus of the work is on the investigation of surface structures, which can be produced during the turning process. The investigation was made in water by means of aluminium and steel components with defined groove surface structures. Geometry of the surface structure was varied. The evaluation was based on time-temperature measurements, and rewetting front observations. It was found that the purposefully structured surface can affect Quenching kinetic considerably. The possibility to homogenize the Quenching process by surface structuring adapted to component geometry was confirmed. This indicates a high potential for homogenizing of immersion Quenching in vaporizing liquids.
Xinghong Zhang - One of the best experts on this subject based on the ideXlab platform.
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an aqueous polymer Quenching Medium for instantaneous thermal shock cooling rate study of ceramic materials
Journal of Alloys and Compounds, 2017Co-Authors: Limin Chen, Fei Zhu, Zhengjun Zhang, Anzhe Wang, Yunhan Ling, Wei Liang, Xiangbo Suo, Xinghong ZhangAbstract:Abstract An aqueous polymer Quenching technique combing with a thermocouple real-time temperature acquisition technique were adopted to evaluate the thermal shock resistance of a hot-pressed ZrB 2 –SiC–graphite composite. The thermal shock behavior of the composite at different testing temperatures could be controlled and adjusted through varying the polymer concentration in the aqueous Quenching solution. Experimental data showed that the critical maximum instantaneous thermal shock cooling rate at different testing temperatures was a constant value of 500 °C s −1 (ν(max) c ), and surface microcracks were assigned to the thermal shock failure. Heat transfer coefficient ( h ) gradient in samples, surface generated under two different Quenching media, i.e. water and aqueous silicone oil solution, resulted in different tendency of decrease in strength. Thermal shock failure was presumed to be related to not only the body temperature gradient but also the surface h gradient in samples to produce thermal stress damage. The results indicate a promising method for studying the thermal shock resistance of ceramic materials.
