利用TDS方法研究氢在两种马氏体钢中的扩散

Investigation of Hydrogen Transport in Two Martensitic Steels by Means of Thermal Desorption Spectrometry

采用TDS方法研究了氢在两种马氏体钢中的扩散行为,结果发现氢在高铬低铝的D2钢中的扩散显著低于低铬无铝的D1钢。从充氢试样室温放置时氢体积分数下降规律可知,氢在D1钢和D2钢中的扩散系数分别为1.52×10-7和5.3×10-8cm2/s。D2钢中存在大量细小的碳化物,既对氢的扩散起到阻碍作用,降低氢的扩散系数,又可作为氢陷阱,使氢含量增加。D2钢的氢脆敏感性低于D1钢。

Hydrogen transport in two martensitic steels was investigated by means of thermal desorption spectrometry.Results show that hydrogen in the steel with a high Cr and low Al content transports obviously more slowly than in the steel with a low Cr and minor Al content.The diffusion coefficient of hydrogen in the D1 steel was determined to be 1.52×10-7 cm2/s,while that in the D2 steel was 5.3×10-8 cm2/s,from the variation of the hydrogen content in the hydrogen charged specimen with exposing time at ambient temperature.There were a large number of fine carbides in the D2 steel,which can prevent hydrogen from diffusing and reduce the hydrogen diffusion coefficient,and they may also act as hydrogen trap sites and increase the hydrogen content charged.Thus,the hydrogen embrittlement susceptibility of the D2 steel is lower than that of the D1 steel.