摘要
对模具钢进行Uddeholm热疲劳试验,发现经不同循环次数后,材料均发生了循环软化,随着循环次数增加,软化更趋严重。同时,晶粒大小也发生了变化,循环100次、2O0次未发现晶粒尺寸变化,循环至300次后,晶粒突然长大,经500次循环后,晶粒尺寸又减小,循环10~3次后晶粒明显碎化。根据上述诸现象,文章用动态回复再结晶理论、空洞理论等进行了解释。
The thermal fatigue tests were performed vsing Uddeholm method in die ste-el. The test results show that after different cycle number cyclic softening wereobserved, increase with cycle in cycling softening became serious and at the sametime grain size changes happened. After 100 cycles and 200 cycles grain sizechange were not observed, but it showed swift grow up in grain size after 300 cy-cles. After 500 cycles grain size smalized, grain size obviously minimized after1000 cycles. These phenomena have already been mentioned above, the paper expl-ained using dynamic recovery, dynamic recrystallization and vacancy theory.
关键词
模具钢
热疲劳
晶粒
软化机制
die steel
thermal fatigue
grain
softening mechanism
