不同Al含量的310S耐热钢热轧加工后的组织和力学性能

Effect of Aluminum content on Microstructure and mechanical properties of 310S heat-resistant steel containing different Al content after hot-rolling

通过压力机和热轧机对WS-4非自耗真空电弧炉熔炼制备的Al质量分数为0、2%、4%、6%的310S耐热钢进行开坯轧制,用光学金相显微镜观察金相组织,用EPMA-1600电子探针分析组织中各元素分布,结合EPMA能谱分析确定合金中的相组成,并测定室温拉伸性能.结果表明:随着Al含量的增加,钢中碳化物的数量明显减少,且形态逐渐由团聚状向颗粒状转变;部分Al元素以Al4C3相的形式出现富集,且Al元素含量越高富集现象越严重;合金的屈服强度略有降低,Al质量分数为2%的合金具有最高的抗拉强度及延伸率.各成分合金的综合力学性能明显高于国家标准对热轧310S板材的要求.

310S heat-resistant steel with 0,2%,4% and 6% aluminum content was prepared in WS-4 non-consumption vacuum arc furnace and then cogged and rolled on press and hot-roller.The microstructure and distribution of elements were investigated by using optical microscopy and EPMA-1600 electron probe,and the phases of alloy were analyzed with energy spectrum analysis of EPMA-1600.The tensile property was tested at room temperature.The result showed that,as the aluminum content increased,the amount of carbide would decrease and the shape of carbide would gradually transform from the spherical aggregates to particles.The aluminum would be enriched in the form of Al4C3 phase,and the phenomenon of Al-rich would become more severe with the aluminum increasing.The yield strength of alloys would decrease slightly,and the steel with 2% aluminum content exhibited the highest tensile strength and elongation.The mechanical property of alloys was obviously higher than that stipulated by national standard of hot-rolled 310S sheet.