Mn-Cu耐候钢的表面龟裂

来源期刊：金属学报2010年第6期

论文作者：王雷 张思勋 董俊华 柯伟 刘春明

文章页码：723 - 728

关键词：Mn-Cu耐候钢； 龟裂； 高温保温； 脱碳

Key words：Mn-Cu weathering steel； surface crazing； soaking； decarbonization

摘    要：通过在1260℃进行的保温实验,研究了Mn-Cu耐候钢的龟裂现象.结果表明,在氧化气氛中经过不同时间高温保温处理,Mn-Cu耐候钢表层均出现了不同程度的龟裂.EPMA结果表明,Cu在基体/氧化皮界面区出现富集,Cu在珠光体中的含量高于铁素体.Mn-Cu耐候钢在高温保温过程中表层发生的脱碳现象导致脱碳层中珠光体析出数量减少,致使过多的Cu在晶界析出偏聚、形成富Cu相,进而加剧钢的表面龟裂.在还原气氛中高温保温处理后,没有发现Mn-Cu耐候钢出现上述现象.

Abstract: Craze cracks and oxidation appeared on the surfaces of the Mn-Cu weathering steel samples after different soaking times at 1260℃ in the oxidizing conditions.EPMA result shows that Cu enriches at the interface of matrix/scale,Cu concentration in pearlite is higher than that in ferrite. OM observation shows that decarbonization phenomenon occurred near surface of steel after soaking in high temperature experiments,which resulted in an obvious decrease of pearlite amount,so more Cu segregation in grain boundaries and formed Cu-enriched phase,and caused serious surface crazing at last.However,under the reducing condition,the craze crack phenomenon did not occur after soaking.