Development of High Fatigue Strength Ti-6Al-4V Alloy Compacts through MIM Process
Although Ti-6Al-4V alloy has excellent mechanical and physical properties,it needs high-cost for machining process to fabricate complex shaped parts.Therefore,the application of Metal Injection Molding(MIM)process is hoped to be desirable.However,the fatigue strength of injection molded Ti-6Al-4V alloy compacts is significantly low and needs to be improved to meet the demands of high-strength structural parts.The authors previously showed that the multiple addition of Mo and B improved the tensile and fatigue properties.But,Mo has the disadvantages of high price and high density.Therefore,Cr,which is the same β stabilizing element as Mo,was added with B,and their influence on the mechanical properties was evaluated in this study.The addition of 4Cr-0.4B exhibited their high density and high tensile properties.However,when the sintering time was prolonged,the decreasing of elongation was also observed.The cause was presumed to be the increase of oxygen content and the coarsening of prior β grains.The room temperature fatigue strength of the 4Cr-0.4B added compacts was equivalent to that of the 4Mo-0.4B added compacts.Furthermore,the high temperature fatigue strength was also evaluated.The 4Cr-0.4B added compacts treated HIP showed the highest fatigue strength of 375 MPa at 260℃.It was found that the multiple addition of β stabilizing elements and boron is effective for improving the high temperature fatigue strength.
Metal Injection Molding Ti-6Al-4V Addition of β stabilizing elements and boron Fatigue strength Microstructure
Kudo Kentaro Shinagawa Kazunari Miura Hideshi
Department of Mechanical Engineering,Graduate School of Kyushu University,744 Motooka,Nishi-ku,Fukuo Department of Mechanical Engineering,Kyushu University,744 Motooka,Nishi-ku,Fukuoka 819-0395,Japan Research Center for Steel,Kyushu University,744 Motooka,Nishi-ku,Fukuoka 819-0395,Japan
国际会议
北京
英文
2132-2136
2018-09-16（万方平台首次上网日期，不代表论文的发表时间）