偏析对27MnCrB5性能的影响

Effect of Segregation on the Properties of 27MnCrB5

对唐钢产的热卷27MnCrB5进行金相组织分析,发现存在珠光体反偏析。通过进行拉伸试验均匀性试验、系列温度冲击试验,确定偏析对性能的影响情况。结果表明,拉伸试验均匀性较好,操作侧、1/4、中间、3/4、传动侧性能波动小;冲击性能温度每降低20℃冲击功降低25 J,-20℃开始出现脆性转变。通过优化成分及改变控轧控冷模式,减少珠光体偏析,改善低温冲击性能。

A metallographic analysis of 27 MnCrB5 produ ce d by Tangshan Stainless Steel Company showed the presence of pearlite reverse segregation.The effects of segregation on performance were determined by the homogeneity test and series temperature impact test.The results showed that the homogeneity of the tensile test was better,and the performance of the operating side,quarter,middle,three-quarters and transmission side fluctuated less.The impact performance temperature decreases by 25 J for every 20℃reduction,and brittle transitions begin at-20℃.By optimizing the composition and changing the cooling mode of the controlled rolling,the pearlite segregation was reduced and the impact performance of the low temperature was improved.