emissary dislocations

TEM observation of dislocation emission and nano-crack nucleation;

位错发射与纳米裂纹形核的TEM实验观察

The results showed that chemisorption of Hg atoms could facilitate dislocation emission and motion.

结果表明：加载裂纹吸附Hg原子后能促进位错的发射、增殖和运动；当吸附促进位错发射和运动达到临界状态时，脆性微裂纹就在原裂纹顶端或在无位错区中形核并解理扩展。

The results showed that chemisorption of liquid metal atoms could facilitate dislocation emission,multiplication and motioll.

结果表明：液体金属吸附后能促进位错的发射、增殖和运动；当吸附促进位错发射和运动达到临界状态时，脆性微裂纹就在原裂纹顶端或在无位错区中形核并解理扩展。

In situ tensile test in TEM showed that a dislocation-free zone (DFZ) formed ahead of a loaded crack tip when dislocation emission and motion reached equilibrium under keeping constant displacement, and a microcrack initiated after the dislocation emission and motion developed to a certain condition through increasing load.

结果表明，氢能促进位错的发射、增殖和运动 和未充氢纯Ｎｉ相比，充氢试样在更低的外应力下位错就会发射和运动，当氢促进的位错发射和运动到临界条件时就会使氢致裂纹形核、扩展，导致低应力脆断。