304L不锈钢晶间腐蚀的临界电位

THE CRITICAL POTENTIAL FOR INTERGRANULAR CORROSION OF 304 STAINLESS STEEL

敏化态３０４Ｌ不锈钢在０．５ｍｏｌ／ＬＨ２ＳＯ４＋１０（－３）ｍｏｌ／ＬＣＨ３ＣＳＮＨ２溶液中晶间腐蚀存在两个敏感电位区间，一个是活化－钝化过渡电位区，另一个敏感电位区间的晶间腐蚀的临界电位值是１０４０ｍＶ（ＳＣＥ），高于这个电位值，材料对晶间腐蚀敏感．用恒电位法可以评价材料晶间腐蚀的倾向，恒电位实验法测量的电流和电流－时间曲线的斜率越大，材料的晶间腐蚀倾向越大．

There are two potential ranges for 304L stainless steel sensitive to intergranular corrosion in 0.5mol / LH2SO4+10(-3)mol/L CH3CSNH2 solution. One is active-passive transitive potential range, the critical potential for the other is 1040mV(SCE). The material is sensitive to intergranular corrosion at potentials above this value. The susceptibility to intergranular corrosion of 304L stainless steel can be judged by potentic-static method. The bigger the current density andthe slope of current density-time curves at a certain potential, the more susceptive to intergranularcorrosion.