论文标题
调查由氢气的Maraging不锈钢中的准裂解
Investigation of quasi-cleavage in a hydrogen charged maraging stainless steel
论文作者
论文摘要
缓慢的应变速率测试（SSRT）是在含氢的PH13-8MO MARAGGENNESS不锈钢标本上进行的。 SSRT期间显示出氢辅助的亚临界裂解裂纹发生，从而加速了材料故障。分形分析表明，准切割是由平坦的脆性区域和更粗糙的区域组成的。使用次级亚批判性裂纹的横截面反向散射衍射（EBSD）分析，我们观察到脆性裂纹在主裂纹尖端前方的马氏体块中传播。这些裂缝在高角度边界停止。裂纹方向与沿{100}类型平面的传播一致。高分辨率EBSD显示出明显的晶体晶格旋转，因此塑性变形，集中在主裂纹尖端和位于其前方的裂缝之间。结论是，此处研究的材料中的准切割包括{100}裂解裂纹通过延性脊连接的裂缝。提出了一种不连续的机制，涉及在主要裂纹尖端前进的新裂解裂纹的重新定位。
Slow strain rates tests (SSRT) were conducted on hydrogen-containing specimens of PH13-8Mo maraging stainless steel. Hydrogen-assisted subcritical quasi-cleavage cracking was shown to take place during SSRT, thus accelerating material failure. Fractographic analysis showed that quasi-cleavage is composed of flat brittle areas and rougher areas. Using cross-sectional electron backscatter diffraction (EBSD) analysis of a secondary subcritically grown crack, we observed brittle cracks propagated across martensite blocks ahead the main crack tip. These cracks were stopped at high-angle boundaries. The crack direction was consistent with propagation along {100} type planes. High-resolution EBSD showed significant crystal lattice rotation, hence consequential plastic deformation, concentrated between the main crack tip and the cracks located ahead it. It is concluded that quasi-cleavage in the material investigated here consists of {100} cleavage cracks connected by ductile ridges. A discontinuous mechanism, involving re-initiation of new cleavage cracks ahead the main crack tip is suggested.
