Ni基P／M Rene 95合金中非金属夹杂物导致裂纹萌生和扩展的扫描电镜原位观察

通过SEM原位拉伸试验观察了P/M Rene 95合金中的非金属夹杂在拉伸状态下导致裂纹萌生、扩展的微观力学行为，结果表明：在原位拉伸过程中，裂纹首先在试样表面的夹杂物处产生，裂纹主要萌生于夹杂物/合金基体的界面；随着外加应力的增加；裂纹极易沿夹杂物/基体界面扩展，向基体深入；最后，部分夹杂与基体完全分离、脱落，一些夹杂物的材料制备过程中被破碎成若干碎片，增加了裂纹萌生的几率。

SEM In-Situ Observation on Crack Initiation and Propagation induced by Inclusion in PM Rene95

The crack initiation and propagation in Al2O3 seeded P/M Rene95 have been studied by SEM observation in-situ for tension loading stage of the P/M Rene95 sample. The results show that during SEM in-situ tension process, cracks initiate at ceramic inclusions. Generally, the cracks nucleate at the inclusion/matrix interface, and easily propagate along the interfaces and reach the matrix. At last, some inclusion particles may separate from the matrix and fall off.