稀土对16Mn钢中氢行为的影响

EFFECTS OF RARE EARTH METAL ON HYDROGEN BEHAVIOUR IN STEEL 16Mn

研究了RE/S分别为0、0.7、2.2和7.7的16Mn钢充氢后的慢拉伸、动态充氢滞后破坏行为以及在不同温度下的放氢行为。结果表明,合适的RE/S能显著地降低16Mn钢的氢脆敏感性,RE/S为2.2左右时,抑制氢脆作用明显。在电解充氢条件下,不含稀土的16Mn钢比含稀土的能吸入更多的氢量且易于放出。用长条状MnS夹杂物与基体界面对氢的“捕获”作用、“短路通道”作用以及稀土对氢的强烈吸附作用对本实验结果进行了分析讨论。

The slow tensile tests, dynamic hydrogen charging tensile tests and hydrogen evolution tests after hydrogen charging were used to study the effects of rare earth metal (REM) on hydrogen behaviour in a steel 16Mn (St. 52). The ratios of RE/S were chosen as 0, 0.7, 2.2 and 7.7, respectively. It was shown that the steel with RE/S=2.2 give a lower hydrogen embrittlement susceptibility than others. The steels without REM can adsorb much more amount of hydrogen than that with REM under the same hydrogen charging conditions. And the amount of adsorbed hydrogen for the former can be evolved easier than that for the latter at room temperature, 50℃ and 80℃, respectively. The experimental results were explained by the trap theory of hydrogen, the short-circuit diffusion paths in the interfaces between the elongated MnS inclusions and the matrix, and strong ability of REM to adsorb hydrogen.