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研究了不锈钢Ⅱ型单晶试样在４２％沸腾ＭｇＣｌ＿２溶液中的应力腐蚀。结果表明，对任何晶面取向的试样，其应力腐蚀裂纹均在最大正应力处形核，而在最大剪应力位置并不发生应力腐蚀．在最大正应力位置的周围虽有滑移线，但在裂纹形核的区域并无滑移线，而在有滑移线的地方却没有宏观裂纹。观察表明，有些滑移线上存在很多蚀坑，在蚀坑较轻微的滑移线上，有许多微裂纹，这些裂纹与滑移线成一定角度（约２０°）．在应力腐蚀裂纹的形核与扩展中起作用的是位错局部塞积所形成的应力集中．位错塞积应力与电化学过程的联合作用下导致了应力腐蚀开裂，金属表面的滑移台阶虽然也会发生腐蚀，但并不起主要作用。
The stress corrosion of stainless steel Ⅱ type single crystal sample in 42% boiling MgCl 2 solution was studied. The results show that for any sample with crystal orientation, the stress corrosion cracking nucleates at the maximum normal stress and no stress corrosion occurs at the maximum shear stress. Although there is a slip line around the location of the maximum normal stress, there is no slip line in the area where the crack nucleation occurs, but there is no macro-crack in the place where the slip line exists. The observation shows that there are many corrosion pits in some slip lines, and there are many micro-cracks on the slightest slippage lines. The cracks are at an angle (about 20 °) to the slip line. In the stress corrosion cracking nucleation and expansion of the work is the formation of dislocation of the local plug the stress concentration. The combined effect of dislocation plugging stress and electrochemical process leads to stress corrosion cracking. Although the sliding step of the metal surface also corrodes, it does not play a major role.