高温合金IN690碳化物析出及对组织的影响

Carbide Precipitation and Its Effect on Structure of Super-alloy IN690

通过对IN690合金进行的固溶处理试验和压缩试验,研究了其合金晶粒组织和碳化物的变化规律以及碳化物对组织均匀性的影响。结果表明:晶粒组织随固溶温度的升高而增大,碳化物含量随温度升高而逐渐减小。当碳化物完全溶解时,晶粒会急剧长大。因而碳化物在晶界处有钉扎作用,限制晶粒的快速长大,对晶粒的均匀性有重要的影响。通过压缩实验分析了不同变形温度和变形速率对碳化物析出的规律影响。随压缩温度的升高晶内碳化物逐步溶解,并向晶界处转移。随变形速率增大,碳化物沿晶界析出增多,当变形温度为1200℃和变形速率为80s-1时,晶粒均匀性较好。

Grain structure and carbide variation,and the effect of carbides on the microstructure uniformity of super-alloy IN690 had been studied by solution treatment tests and compression tests.The results revealed that the dimension of grain size increased with increasing of solution temperature,but carbide content gradually decreased with rising of temperature.When carbide was completely dissolved,the grains grew rapidly.Pinning effect of carbides at grain boundary restricted grains growing rapidly,which had an important influence on the uniformity of crystal grains.The laws of influence on carbide precipitation with different temperatures and deformation rate were also analyzed through compression tests.Intragranular carbide dissolved gradually with increasing of deformation temperature and transfered to the grain boundary.With increasing of deformation rate,carbide precipitates increased in grain boundary.The grain uniformity was better when deformation temperature was at 1200℃ and strain rate was 80s-1.