开发了一种串联电化学充氢方法, 可以一次性有效地对试样进行充氢, 新充氢方法有效解决了以往电化学充氢方法中试样的氢含量不均匀问题; 将放入加氢反应器中运行了10万h的2.25Cr-1Mo钢块脱脆后, 再在468 ℃脆化200 h, 制备了四种状态的脆化试样, 即200 h回火脆化、应力作用下200 h回火脆化、200 h回火脆化后充氢以及应力作用下200 h回火脆化后充氢试样, 并对四种状态试样分别进行冲击试验、俄歇电子能谱分析。结果表明: 应力减弱了2.25Cr-1Mo合金钢的回火脆化程度, 充氢大大加速了其脆化程度;其原因是磷原子偏析造成的。

A series electrochemical hydrogen charging method was developed, which could be effectively carried out with several samples at the same time. The new method could availably resolve the problem of uneven hydrogen concentration in the sample charged by the previous method of electrochemical hydrogen charging. 2.25Cr-1Mo steel samples in 4 kinds of state, i.e., temper embrittlement for 200 h, temper embrittlement for 200 h under stress, hydrogen charging after temper embrittlement for 200 h and hydrogen charging after temper embrittlement for 200 h under stress were prepared. Before the sample preparation, a 2.25Cr-1Mo block had been put in the running hydrogenation reactor for 100 000 h and then the de-brittled steel was embrittled at 468 ℃ for 200 h. Impact tests and Auger electron spectroscopy were performed for the 4 states of samples. The results show that stress could reduce the degree of temper embrittlement of the 2.25Cr-1Mo steel, while hydrogen charging could accelerate it. The reason was phosphous segregation.