金属内氢扩散过程的边界元分析

本文采用边界元素法。对金属内氢的扩散过程进行了分析与计算,给出了裂尖附近氢的聚集过程及氢浓度分布随时间变化的定量关系,结果表明,裂尖塑性区内氢浓度随扩散时间的增加而升高,在一定时间范围内,裂纹前缘氢浓度会出现多峰值现象,随着时间推移,塑性区内会出现氢的高度浓集,这是导致金属材料氢脆破坏的根源所在。文中还与有关的试验现象和结果进行了比较与讨论。进一步探讨了金属的氢脆裂纹扩展机制。

An Analysis of Hydrogen Diffusion Process in Metals by Boundary Element Technique

In this paper, the boundary element technique is used to analyse and calculate hydrogen diffusion in metallic materials. In result, the quantitative relationship of hydrogen concentration distribution as a function of time is obtained, It is shown that the hydrogen concentration distribution in the plastic zone increases with diffusion time. In a certain period of time, there can exist multiple peak values of hydrogen concentration in front of the crack tip. As time goes on, there will be a high degree of hydrogen aggression near the crack tip, which is the basic reason of hydrogen embrittlement failure of metallic materials. Based on the obtained results, the mechanism of hydrogen embritllement of metals is further discussed, The analytical results are also compared with some experimental results.