应用方波电位脉冲方法检测304L奥氏体不锈钢晶间腐蚀敏感性

Determing the Susceptibility of 304L Austenitic Stainless Steel to Intergranular Corrosion by Square-wave Potentiostatic Pulse Technique

摘要: 用方波电位脉冲法,对AISI304L不锈钢主要由晶界贫铬引起的晶间腐蚀敏感性随敏化时间的变化规律进行了研究。通过比较发现方波电位脉冲实验与EPR方法、10%草酸电解实验以及H₂SO₄-CuSO₄-钢屑实验之间存在着较好的对应关系。方波电位脉冲法可以精确地定量反映304L不锈钢的晶间腐蚀敏感性,对应第10个脉冲的再活化电流密度峰值i_r10可作为反映晶间腐蚀敏感性的特征参数。

Abstract: The susceptibility of AISI 304L austenitic stainless steel to intergranular attack mainly caused by the Cr-depletion in grain boundaries was detected by the square-wave potentiostatic pulse technique. The degree of the sensitization of 304L stainless steel can be exactly and quantitively illustrated by this technique.The maximum reactivation current density corresponding to 10th pulse,ir10,was selected as a characteristic parameter for the detection of sensitization.The degree of the sensitization determined by square-wave potentiostatic pulse technique was in agreement with those obtained from DL-EPR and ASTM standard tests.