摘要
对冷轧 60 %IC - 2 1 8合金 (一种含 1 5 %～ 2 0 %共格γ相的γ′ +γ两相合金 )在 875～ 1 0 0 0℃温度范围内的再结晶动力学研究表明 :该合金在退火早期即可大量形核 ,但随后的再结晶进展非常缓慢。在Xv=2 0 %～ 60 %的阶段 ,用Avrami方程Xv=1 exp [-Btk]来描述 ,k值呈 0 2 4的异常小值。新晶粒的界面迁移速率在迁移过程中不断下降 ,以至最后几乎停止迁移。 1 0 5 0℃ 72小时退火也不会造成明显晶粒粗化。这表明该合金具有很强的高温下抗晶粒粗化的能力。
Recrystallization kinetics was studied of IC 218 alloy(a Ni 3Al ( B ) Cr base alloy containing 15～20% coherent γ phase)which was cold rolled 60% and annealed at temperatures from 875℃ to 1000℃.It was found that,although recrystallization started readily with preferential nucleation at shear bands or original grain boundaries,the progress of recrystallization was very sluggish soon afterward.In the ranges of X v=20～60%,if the process was described in terms of Avrami equation X v=1-exp,an unusually low value of k=0 24 was showed.The migration rate of new grains continuously decreased,many of them even stopped growing at a certain size and remained unchanged during long annealing time.The annealing of IC 218 alloy at 1050℃ for 72 hours did not cause remarkable grain coarsing,which implied that it possessed strong ability to resist grain coarsing at high temperature.TEM observation revealed the unusual behavior of boundary migration in IC 218 alloy.[
出处
《上海金属》
CAS
2002年第3期8-12,共5页
Shanghai Metals
