Internal hydrogen embrittlement of a ferritic stainless steel
Internal hydrogen embrittlement of a ferritic stainless steel
复制标题
铁素体不锈钢的内部氢脆
DOI：
10.1007/bf02649081
复制
发表时间：
1995
期刊：
影响因子：
--
通讯作者：
C. Altstetter
中科院分区：
文献类型：
--
作者：
Jia;C. Altstetter
AL 29-4-2铁素体不锈钢在熔融盐电解质中在230 ℃下阴极预充氢。在空气和氢气中在室温下在108 kPa压力下对未充电的试样和含有2 wtppm氢的试样进行恒定载荷裂纹扩展测试。采用光学测量方法对直流电位降法进行标定，以连续监测裂纹位置，从而计算出裂纹速度与应力强度的关系。根据试验结果，发现溶解氢确实允许在空气中进行试验的亚临界裂纹扩展，但其效果被氢气中的试验的外部氢所掩盖。侧表面滑移带的分布表明，溶氢导致塑性局部化，应变集中在粗大的滑移带中。比较内部氢与外部氢的脆化效果，可以得出结论，环境氢比内部氢更有害，至少在含有2重量ppm氢的试样中。
AL 29-4-2 ferritic stainless steel was cathodically precharged with hydrogen at 230 ‡C in a molten salt electrolyte. Constant load crack growth tests were performed in air and in hydrogen gas at 108 kPa pressure at room temperature on both uncharged specimens and specimens containing 2 wt ppm hydrogen. The DC potential drop method was calibrated with optical measurements to continuously monitor the crack position, so that the crack velocity vs stress intensity relation could be calculated. From the test results, it was found that dissolved hydrogen does allow subcritical crack growth for tests in air, but its effect is masked by the external hydrogen for tests in hydrogen gas. The distribution of slip bands on the side surface indicates that the dissolved hydrogen causes localization of plasticity, with the strain concentrated in coarse slip bands. Comparing the embrittling effect of internal hydrogen with that of external hydrogen, it can be concluded that environmental hydrogen is far more damaging than internal hydrogen, at least in specimens containing 2 wt ppm hydrogen.