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用自制的恒位移试样在TEM中原位研究了充氢前后位错组态的变化以及氢致微裂纹形核和位错运动及无位错区（DFZ）的关系．结果表明，氢能促进位错发射、增殖和运动．当氢促进的位错发射和运动达到临界条件时，氢致裂纹就在DFZ中或原缺口顶端形核．这个过程和空气中原位拉伸相类似，但氢的存在使得在较低的外应力下氢致裂纹就能形核．
The self-made constant displacement samples were used to study the changes of dislocation configurations and the nucleation of hydrogen induced microcracks and the dislocation motion and dislocation-free region (DFZ) in situ before and after hydrogen charging. The results show that hydrogen promotes dislocation emission, proliferation and motility. When hydrogen-promoted dislocation emission and motion reach critical conditions, the hydrogen-induced cracks nucleate in the DFZ or at the apical notch. This process is similar to in-situ stretching in air, but the presence of hydrogen allows the nucleation of hydrogen-induced cracks at lower external stresses.