摘要
利用Gleeble-1500D热模拟试验机研究了Ti-44Al、Ti-44Al-6Nb和Ti-44Al-6Nb-1Cr-2V合金在1 100～1 250℃和0. 01 s-1条件下的热变形行为。研究结果表明,添加β相稳定元素可降低TiAl合金的流变应力,在相同变形条件下Ti-44Al-6Nb-1Cr-2V合金具有更低的峰值应力。高温变形时,TiAl合金主要发生片层弯曲和拉长协调变形,以及片层团晶界处动态再结晶和B2相协调变形。动态再结晶程度随着变形温度的升高以及β相稳定元素含量的提高而增加,B2相协调变形和促进动态再结晶是TiAl合金的主要软化方式。添加β相稳定元素和控制B2相含量能有效改善TiAl合金热加工性能。
The hot deformation behavior of Ti-44Al,Ti-44Al-6Nb and Ti-44Al-6Nb-1Cr-2V alloys was studied on a Gleeble-1500D hot simulation machine at the temperature range of 1 100~1 250℃and 0.01 s-1.The results show that Ti-44Al-6Nb-1Cr-2V alloy shows the lower peak stress comparing to Ti-44Al alloy and Ti-44Al-6Nb alloy under the same deformation condition indicating that beta phase stabilizing elements can reduce flow stress of TiAl alloys significantly.The lamellar is bending and elongation to coordinate deformation during hot deformation,and dynamic recrystallization is mainly occurred at the lamellar colony.The dynamic recrystallization increases with the increase of the deformation temperature and beta phase stabilizing element content.B2 phase coordination deformation and promoting dynamic recrystallization are the main softening mechanism for TiAl alloys at high temperature.Thus addition of beta phase stabilizing elements and controlling of B2 phase can effectively improve the hot workability of TiAl alloys.
作者
马腾飞
陈瑞润
Ma Tengfei;Chen Ruirun(Harbin Institute of Technology,Harbin 150001,China;Northwest Institute for Nonferrous Metal Research,Xi’an 710016,China)
出处
《钛工业进展》
CAS
北大核心
2019年第1期40-43,共4页
Titanium Industry Progress
