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 microhardness of T...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 microhardness 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 about52.7 nm was obtained eventually,and no obvious formation of metastableωphase was detected by XRD analysis.For the first time,the tribological properties of the HPT processed Ti6Al4V alloy were investigated 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 specific wear rate were obviously decreased due to the reduction of abrasion and adhesion wears.After being deformed by 10 HPT revolutions,the friction coefficient was reduced from about 0.49 to 0.37,and the specific wear rate was reduced by about 48%.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.展开更多
基金Australian Academy of Science(AAS)and Japan Society for the Promotion of Science(JSPS)for awarding him an international fellowship and financial supportAustralian Research Council(ARC)for awarding her the Discovery Early Career Researcher Award(DECRA)fellowship(grant no.DE180100124)+2 种基金the financial supports from the Cross-ministerial Strategic Innovation Promotion Program(SIP)from the Cabinet Office of Japanese government,the Elements Strategy Initiative for Structural Materials(ESISM,No.JPMXP0112101000)in Kyoto University from the Ministry of Education,Culture,Sports,Science and Technology(MEXT),JapanJST CREST(JPMJCR1994)from Japan Science and Technology Agency(JST)partly supported by Open Research Fund of State Key Laboratory of High Performance Complex Manufacturing,Central South University in China。
文摘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 microhardness 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 about52.7 nm was obtained eventually,and no obvious formation of metastableωphase was detected by XRD analysis.For the first time,the tribological properties of the HPT processed Ti6Al4V alloy were investigated 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 specific wear rate were obviously decreased due to the reduction of abrasion and adhesion wears.After being deformed by 10 HPT revolutions,the friction coefficient was reduced from about 0.49 to 0.37,and the specific wear rate was reduced by about 48%.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.
