氢陷阱对纯净钢SM490B中氢扩散行为的作用

EFFECT OF HYDROGEN TRAPS ON DIFFUSION OF HYDROGEN IN SM490B CLEAN STEEL

利用电化学氢渗透法研究了氢陷阱对纯净钢SM490B中氢扩散的影响,研究结果表明,在SM490B钢中不可逆氢陷阱对氢的表观扩散系数没有影响,但会延长氢原子的穿透时间,而可逆氢陷阱则降低了氢的表观扩散系数。当氢渗透电流密度小于8 mA/cm^2时,随充氢电流密度增加,氢原子的表观扩散系数随之增大;当氢渗透电流密度大于8 mA/cm^2后,随着氢渗透电流密度的增大,氢在SM490B钢中的表观扩散系数保持恒定。在温度30℃时,氢原子在无氢陷阱的纯净钢SM490B理想晶格中的扩散系数为3.97×10^(-5)cm^2/s。

The effect of hydrogen traps in SM490B clean steel on the hydrogen diffusivity was studied by the electrochemical permeation methods. Results indicated that the reversible hydrogen trap decreased the apparent diffusion coefficient of hydrogen, while the irreversible hydrogen trap only delayed the penetrating time of hydrogen. These results also showed that the apparent diffusion coefficient of hydrogen increased with the increasing of cathode current density （i） when i was between 1 and 8 mA/cm2, but kept constant after i ≥ 8 mA/cm2. The diffusion coefficient of hydrogen was 3.97 × 10-5 cm2/s in the ideal lattice of SM490B clean steel at 30 ℃.