As a significant cause of disastrous accidents, stress corrosion cracking (SCC) under elastic loads was investigated in type 316 L single-crystal stainless steel immersed in a boiling 45 wt% MgCl₂ solution. Three-dimensional microcrack morphologies, characterized using synchrotron-based X-ray computed tomography, indicate that the SCC advanced along the cleavage planes (1 0 0) with the lowest free surface energy. The first-principles simulations show that synergistic adsorption of H and Cl atoms in the octahedral interstices minimized the surface energy of the cleavage planes (0 0 1) owing to a 73% reduction. Afterwards, the cleavage-dissolution mechanism is put forward, proposing that the SCC essentially originates from preferential brittle rupture of the corrosive environment particle adsorbed low-surface-energy cleavage planes in the elastic stress concentration zones, and anodic dissolution along the crack fronts. Besides, the corrosive environment particles primarily consist of the hydrogen atoms and the electronegative ions such as the chlorine ions.

作为灾难​​性事故的重要原因，我们研究了浸入45 wt％MgCl _2的316 L型单晶不锈钢在弹性载荷下的应力腐蚀开裂（SCC）。解决方案。使用基于同步加速器的X射线计算机断层扫描表征的三维微裂纹形态表明，SCC沿着分裂平面（1 0 0）前进，具有最低的自由表面能。第一性原理模拟表明，由于八面体间隙中H和Cl原子的协同吸附，裂隙平面（0 0 1）的表面能由于73％的降低而最小化。提出了裂解溶解机制，认为应力腐蚀开裂本质上是由于腐蚀环境颗粒在弹性应力集中区吸附的低表面能裂解面的优先脆性破裂以及沿裂纹前沿的阳极溶解所致。除了，