α-Fe中置换式合金元素的氢陷阱效应

HYDROGEN TRAPPING EFFECT OF SUBSTITUTIONAL ALLOYING ELEMENTS IN α-Fe

用电化学渗氢方法测定了氢在纯Fe和Fe-Cr,Mn,Co,Si,Mo的二元合金中的扩散系数。结果表明所研究的二元铁基合金中,随着合金元素浓度的增加,氢的扩散系数降低,氢的扩散激活能增加。根据Oriani模型计算了各种合金元素的氢陷阱参数,并获得了相应的氢与陷阱结合能。按陷阱结合能由小到大的顺序是:Si,Co,Ni,Mn,Cr和Mo。最后根据合金元素引起的晶格应变场与氢的弹性交互作用和合金元素与氢的电性交互作用对结合能的本质进行了分析。

The effect of Cr, Mn, Co, Ni, Si or Mo on the diffusivity of hydro- gen in α-Fe has been studied near room temperature by means of sensitive electro- chemical method. With the of increases concentration of alloying elements, the hydro- gen diffusivity in binary Fe alloys decreases and the activation energy increases. On the basis of Oriani's approach, the trapping parameters of the alloying elements in the Fe alloys are calculated and the trap binding energy between the above elements and hydrogen are obtained. The increasing sequence of trap binding energy is as follows: Si, Co, Ni, Mn, Cr, Mo. Finally, the nature of the trap binding energy is analyzed according to both the interaction between lattice strain field induced by alloying elements and hydrogen elasticity as well as the interaction between alloy- ing elements and hydrogen electricity.