定向凝固NiAl-Cr(Mo)-Hf合金的显微组织与力学行为

Microstructure and Mechanical Properties of Directionally Solidified NiAl-Cr(Mo)-Hf Alloy

研究了定向凝固NiAl-Cr(Mo)-Hf合金及其热处理后的显微组织和力学性能。结果表明:热处理后,NiAl基体与Cr(Mo)相中均有第二相析出,胞界上不连续分布的Heusler相(Ni2AlHf)消失,NiAl和Cr(Mo)层片状组织形貌基本没有变化,但Cr相有增厚的趋势。当应变速率为2.78×10-3 s-1时,随着温度的升高,DSNiAl-Cr(Mo)-Hf合金的压缩屈服强度降低。

The microstructure and mechanical properties of directionally solidified NiAl-Cr（Mo）-Hf alloy and its heat treated alloy were studied.The results expatiate that the NiAl matrix and Cr（Mo） phase have both the second phase separation after heat treatment,and the Heusler（Ni2AlHf） phase at the cell boundary disappears,but the lamellar microstructure of NiAl and Cr（Mo） does not change basically,and Cr phase has the accumulated tendency.At the strain rate of 2.78×10-3 s-1,the compression yield strength of DS NiAl-Cr（Mo）-Hf alloy reduces along with temperature increasing.