论文部分内容阅读
在566℃、0.2%恒定应变条件下对GH4145合金进行2000 h拉伸应力松弛试验。结果表明:该合金具有良好的抗应力松弛性能。应力松弛试验前,GH4145合金由等轴晶组成,且晶粒大小不均匀,存在着尺寸相差较大的大、小2种晶粒。应力松弛试验后,小尺寸晶粒明显长大,致使合金的平均晶粒尺寸显著增大。应力松弛试验过程中,GH4145合金中各种形态和尺寸的二次γ′相长大缓慢,立方形二次γ′相的体积分数稍有增大,同时析出了尺寸更加细小的球形三次γ′相,致使合金的硬度升高。
The GH4145 alloy was subjected to 2000 h tensile stress relaxation test at 566 ℃ and 0.2% constant strain. The results show that the alloy has good stress relaxation resistance. Before the stress relaxation test, GH4145 alloy is composed of equiaxed grains, and the grain size is not uniform. There are two kinds of large and small grains with big difference in size. After the stress relaxation test, the small size grains grow obviously, which leads to the significant increase of the average grain size of the alloy. In the process of stress relaxation test, the secondary γ ’phases of various shapes and sizes in GH4145 alloy grow slowly and slowly, the volume fraction of the cubic γ’ phase increases slightly, meanwhile, the spherical third γ ’ Phase, resulting in increased hardness of the alloy.