Hot Tensile Behaviors and Microstructure Evolution of Ti-6Al-4V Titanium Alloy Under Electropulsing  

作　　者：Dong-Wei Ao Xing-Rong Chu Shu-Xia Lin Yang Yang Jun Gao Dong-Wei Ao;Xing-Rong Chu;Shu-Xia Lin;Yang Yang;Jun Gao(Associated Engineering Research Center of Mechanics and Mechatronic Equipment, Shandong University;A Key Laboratory of Optoelectronic Materials Chemistry and Physics, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Science)

机构地区：[1]Associated Engineering Research Center of Mechanics and Mechatronic Equipment, Shandong University [2]A Key Laboratory of Optoelectronic Materials Chemistry and Physics, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Science

出　　处：《Acta Metallurgica Sinica(English Letters)》2018年第12期1287-1296,共10页金属学报（英文版）

基　　金：supported by the Natural Science Foundation of Shandong Province(No.ZR2016EEM25)

摘　　要：The effect of electropulsing on the mechanical behaviors and microstructures of Ti-6Al-4V titanium alloy was investigated by an uniaxial tensile test. Compared to the value measured in cold tensile test, the alloy exhibits lower ultimate tensile strength when the tensile deformation is assisted by electropulsing. The tensile elongation is found to vary non-monotonically with increasing root mean square(RMS) current density. Though decreasing at first, the tensile elongation increases with current density once the value exceeds 8.1 A/mm^2. Through applying current with RMS current density of 12.7 A/mm^2, the tensile elongation at strain rate 0.001 s^(-1) can be improved by 94.1%. In addition, it is observed that more remarkable electroplastic effect is induced by the higher peak current density under similar thermal effect. Microstructure analysis reveals that the low plasticity at 8.1 A/mm^2 is attributed to the micro-void easily formation near the tips of acicular β phases. The enhanced ductility at higher current densities, on the other hand, is attributed to the dynamic recrystallization.The effect of electropulsing on the mechanical behaviors and microstructures of Ti-6Al-4V titanium alloy was investigated by an uniaxial tensile test. Compared to the value measured in cold tensile test, the alloy exhibits lower ultimate tensile strength when the tensile deformation is assisted by electropulsing. The tensile elongation is found to vary non-monotonically with increasing root mean square（RMS） current density. Though decreasing at first, the tensile elongation increases with current density once the value exceeds 8.1 A/mm;. Through applying current with RMS current density of 12.7 A/mm;, the tensile elongation at strain rate 0.001 s;can be improved by 94.1%. In addition, it is observed that more remarkable electroplastic effect is induced by the higher peak current density under similar thermal effect. Microstructure analysis reveals that the low plasticity at 8.1 A/mm;is attributed to the micro-void easily formation near the tips of acicular β phases. The enhanced ductility at higher current densities, on the other hand, is attributed to the dynamic recrystallization.

关 键 词：Ti-6Al-4V alloy ELECTROPULSING Mechanical properties Microstructure Fracture morphology 

分 类 号：TG146.23[一般工业技术—材料科学与工程]