Effect of Heat Treatment Processes on Microstructure and Mechanical Behavior of TC21 Titanium Alloy

• 作者: Azza F. Barakat Khaled M. Ibrahim Ramadan N. Elshaer Reham R. Abbas
• 来源期刊: 金属学报(美国)
• 学科: 工学
• 关键词: TC21 Ti-Alloy COOLING Rate Aging MICROSTRUCTURE TENSILE Properties WEAR
• 年，卷（期）: jsxbmg_2017,（3）
• 页码范围: 39-57
• 页数: 19页
• 分类号: TG14

摘要

The effect of heat treatment on microstructure and tensile properties as well as wear behavior on TC21 (Ti-6Al-2Sn-2Zr-3Mo-1Cr-2Nb-Si, wt.%) Ti-alloy was investigated. The samples were solution treated at 900°C for 15 min followed by furnace cooling to 800°C with a cooling rate 1°C/min and holding for 20 min, then the samples cooled down to room temperature either using water quenching (WQ) or air cooling (AC). Consequently, aging treatment was applied at 575°C for 4 hr. The microstructure feature showed a secondary α phase (αs) precipitated in residual β phase due to the step cooling from 900°C to 800°C inside furnace as well as the aging treatment. The highest wear rate was obtained for WQ samples due to increasing in volume fraction of αp (58%). However, the lowest wear rate was reported for WQ + Aging samples due to the high hardness. Optimum mechanical properties of the studied TC21 Ti-alloy were obtained for AC + Aging condition. A better combination of hardness, tensile properties, and wear resistance was achieved for AC + Aging samples, although their wear resistance was found to be slightly lower than that of WQ + Aging samples.