【摘要】 通过电化学渗氢技术研究了施加不同阴极电位条件下含不同H2S浓度的3.5%NaCl溶液中X70管线钢的氢渗透行为.结果表明,稳态渗氢电流P∞随H2S浓度的增大而逐渐增大,但一定时间内,渗透过试样的氢原子摩尔数并不随之单调增加;氢原子的渗透受到阴极电位的控制,阴极电位越负,渗氢电流越大;在一定电位范围内,稳态渗氢电流P∞和一定时间内渗透过试样的氢原子摩尔数N与阴极电位呈线性关系.扩散系数与试验条件无关.更多还原

【Abstract】 The hydrogen entry and permeation for X70 grade pipeline steels has been investigated electrochemically using a Devanathan cell with a membrane covered on the exit side by a nickel layer.The tests were conducted in 3.5% NaCl solution containing various concentration of H₂S at various applied potential.The results showed that the steady state permeation current P_∞ increased with increasing the content of H₂S,and the permeated hydrogen atoms N didnt increase monotonously within a definite period of time.The hydrogen entry and permeation depended strongly upon the cathodic potential.The more negative the potential was,the higher the steady state permeation current P_∞ was.The steady state permeation current P_∞ and the permeated hydrogen atoms N were linear with cathodic potential over a limited range of potential.The diffusion coefficient was determined by the nature of material and metallurgical factors rather than the test conditions.更多还原