新型汽车排气系统用铁素体不锈钢的冷凝液腐蚀

来源期刊：钢铁2009年第10期

论文作者：陈超 尚成嘉 宋欣 毕洪运 范光伟 侯豁然

文章页码：78 - 81

关键词：铁素体不锈钢； 汽车排气系统； 冷凝液； 点蚀； 极值分析

Key words：ferritic stainless steel； automotive exhaust system； condensate； pitting； extreme value analysis

摘    要：为了开发既经济又具有良好耐冷凝液腐蚀性能的汽车排气系统用不锈钢,采用冷凝液腐蚀试验方法,对一系列的铁素体不锈钢进行了10周期的腐蚀评价研究。研究结果表明:Cr当量高于17%的铁素体不锈钢与Cr的质量分数为17%的铁素体不锈钢耐冷凝液腐蚀性能相当,且平均腐蚀失重量均小于6 g/m²,平均最大腐蚀深度均小于0.03 mm。在此试验结果的基础上,对新开发的439M型铁素体不锈钢和409L型铁素体不锈钢进一步开展5、10、20周期的冷凝液腐蚀试验,并使用极值分析方法对三种周期冷凝液腐蚀试验后样品的最大点蚀深度进行统计分析,研究结果表明,新开发的439M型铁素体不锈钢的预测寿命是409L的1.6倍。

Abstract: To develop new economical stainless steels with good automotive exhaust gas condensate corrosion resistance.The corrosion resistance of a series of ferritic stainless steels was evaluated by a 10-cycles condensate corrosion test.As a result,the condensate corrosion resistance of ferritic stainless steels containing more than 17% Cr was almost the same as the ones contained 17% Cr.Moreover,the average corrosion lost weight was lower than 6 g/m² and the average maximum corrosion depth was less than 0.03 mm for the two types of ferritic stainless steels.According to the test result,the new developed type 439M stainless steel and type 409L stainless steel were studied in the condensate corrosion test for 5 periods,10 periods and 20 periods respectively.The maximum pitting depths on the surface of samples after various period corrosion tests were calculated by extreme value analysis to evaluate the maximum pitting depth of the whole muffler.The result indicates that the longevity of 439M stainless steel is 1.6 times of 409L stainless steel.