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本文通过增广应变试验来研究HY-130焊件中氢脆裂纹的起源及扩展。在焊缝金属所发现的裂纹扩展形态表明,由于位错的堆垛会在界面形成裂纹。而且,特别大的塑性应变总是伴随着裂纹扩展。为证实这一观察,对用电解法充氢或无氢的HY-130钢试样进行了增广应变开裂试验,测量了试样缺口根部的塑性应变。果然,此塑性应变具有明显的滞弹性并且显示出与氢脆相同的对氢含量和应变速率的依赖性,即随着氢含量增加且应变速率降低,塑性应变增加。然而,氢对试样的硬度无影响。本文根据这些观察结果对氢脆的机理进行了讨论。
In this paper, the origin and expansion of hydrogen embrittlement crack in HY-130 weldment are studied through augmented strain test. Crack propagation patterns found in weld metal indicate that cracks may form at the interface due to stacking of dislocations. Moreover, particularly large plastic strains are always accompanied by crack propagation. To confirm this observation, a widening strain-cracking test was performed on HY-130 steel samples electrolytically charged with or without hydrogen and the plastic strain at the root of the notches was measured. Sure enough, this plastic strain has significant anelasticity and exhibits the same dependence on hydrogen content and strain rate as hydrogen embrittlement, ie as the hydrogen content increases and the strain rate decreases, the plastic strain increases. However, hydrogen has no effect on the hardness of the sample. Based on these observations, this article discusses the mechanism of hydrogen embrittlement.