Ti-48Al粉末压坯烧结过程的内耗行为研究

Study on Internal Friction Behavior of Ti-48Al Green Compact during Sintering Process

利用内耗测量技术研究了Ti/Al二元复合粉末压坯的烧结行为。升温测量过程中发现了两个典型的内耗峰,然而这两个内耗峰在随后的降温测量过程都消失了。实验结果表明,低温内耗峰的内耗机制为Al/Al颗粒之间烧结颈的形成,即再结晶过程;高温内耗峰产生于Ti/Al颗粒之间的固相扩散反应(Kirkendall效应)和Ti/Ti颗粒之间的再结晶过程,是一种综合机制。

Ti-Al binary powder sintering behavior was studied by internal friction （IF） measurements. It is found that two obvious IF peaks were observed in IF curves during heating while both the two IF peaks vanish in the subsequent cooling in Ti48Al green compact. The results show that the low temperature IF peak （PL） originates from transformation from mechanical bonding to metallurgical bonding between Al powder particles, which is named recrystallization. The high temperature IF peak （ PH ） is the result of two factor comprehensive action of solid phase diffusion at the Ti/Al interface （the process is also named Kirdendall effect） and recrystallization between Ti powder particles.