Effect of high pressure torsion process on the microhardness,microstructure and tribological property of Ti6Al4V alloy

• 作者: Guanyu Deng Xing Zhao Lihong Su Peitang Wei Liang Zhang Lihua Zhan Yan Chong Hongtao Zhu Nobuhiro Tsuji
• 来源期刊: 材料科学技术（英文版）
• 年，卷（期）: 2021,（35）
• 页码范围: 183-195
• 页数: 13页
• 语种: 英文

摘要

In the present study,a fully lamellar Ti6Al4V alloy was severely deformed by high pressure torsion (HPT)process under a pressure of 7.5 GPa up to 10 revolutions.Experimental results revealed that the micro-hardness of Ti6Al4V was increased remarkably by about ～41％ and saturated at about 432 Hv after the HPT process.A relatively uniform bulk nanostructured Ti6Al4V alloy with an average grain size of about 52.7 nm was obtained eventually,and no obvious formation of metastable ω phase was detected by XRD analysis.For the first time,the tribological properties of the HPT processed Ti6Al4V alloy were investi-gated by a ball-on-disc test at room temperature under a dry condition.It was found that HPT process had a great influence on the friction and wear behaviors of Ti6Al4V alloy.With increasing the number of HPT revolutions,both friction coefficient and spedfic wear rate were obviously decreased due to the reduction of abrasion and adhesion wears.After being deformed by 10 HPT revolutions,the friction co-efficient was reduced from about 0.49 to 0.37,and the specific wear rate was reduced by about 48g.The observations in this study indicated that HPT processed Ti6Al4V alloys had good potential in structural applications owing to their greatly improved mechanical and tribological properties.