醋酸浓度和温度对超级13Cr不锈钢电化学腐蚀行为的影响

摘要

Electrochemical techniques were used to investigate the influence of HAc concentration and solution temperature on the passive and pitting corrosion behavior of super 13Cr stainless steel in 3.5％ NaCl solution.The results revealed that the addition of HAc lowered the open circuit potential of super 13Cr stainless steel,while did not significantly reduce its critical breakdown potential.In the absence of HAc,the passive film exhibited n-type semiconducting property,whereas changed to n + p type in the presence of HAc.With the increase of HAc concentration,the steady state thickness of the passive film decreased while the concentration of point defects in the passive film increased,which indicated the decline of the protective effect of the film.In the absence of HAc,the width of the passive region decreased with the increase of temperature.However,in the presence of HAc,the width of the passive region kept almost unchanged with the uncrease of temperature.%采用电化学方法,研究了醋酸的加入量及温度对于超级13Cr油管钢在3.5％ NaCl(质量分数,下同)溶液中钝化及点蚀行为的影响.结果表明:醋酸的加入引起超级13Cr油管钢开路电位下降,但未显著降低其点蚀电位.不含醋酸时,试样的钝化膜呈n型半导体特性;加入1％和10％的醋酸后,钝化膜呈现n+p型的双极性特征.醋酸会使钝化膜减薄,膜内点缺陷密度增大,从而降低钝化膜的保护作用.溶液中不含醋酸时,升高温度会导致钝化区间变窄,但在含1％醋酸的溶液中,试样的钝化区间宽度随温度升高几乎不变.