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在空气中以及在有阴极电位臣低循环频率为0.1赫芝的情况下的3.5％NaCl溶液中,研究了HY130钢的焊件于不同应力比下的疲劳裂纹增长。这些试验结果与在相似试验条件下的基体金属的裂纹增长数据作了比较。在空气中,疲劳裂纹增长速率在焊缝金属中比在基体金属中慢,特别是在低的应力强度因子范围内更是如此。在最高应力比为0.9的情况下,焊缝金属和基体金属的裂纹增长速率几乎相同。焊缝金属中裂纹增长速率较低是由于残余应力引起的。在盐水环境中,发现了类似的关系,但最高应力比为0.9的情况除外,此时在焊缝金属中裂纹增长得快得多。在持续载荷下,柱状枝晶晶界对环境开裂的敏感性被认为是加速裂纹增长的一个原因。
The fatigue crack growth of HY130 steel at different stress ratios was investigated in air and in 3.5% NaCl solution with a cathode potential of 0.1 Hz. These test results are compared with the crack growth data of the base metal under similar test conditions. In air, the rate of fatigue crack growth is slower in the weld metal than in the base metal, especially in the low stress intensity range. In the case of the highest stress ratio of 0.9, the crack growth rate of the weld metal and the base metal is almost the same. The lower rate of crack growth in weld metal is due to residual stress. A similar relationship was found in the brine environment, except for the case where the maximum stress ratio was 0.9, at which time the crack growth in the weld metal was much faster. Under continuous loading, the susceptibility of columnar dendrite boundaries to environmental cracking is believed to be one of the causes of accelerated crack growth.