Nb对重载车用低合金铸钢组织及力学性能影响  

Effect of Nb on Microstructure and Mechanical Properties of Low Alloy Cast Steel for Heavy-Duty Vehicles

作　　者：张家成 金洋帆[1] 赵天天 杨弋涛[1] ZHANG Jia-cheng;JIN Yang-fan;ZHAO Tian-tian;YANG Yi-tao(School of Materials Science and Engineering,Shanghai University,shanghai 200444,China)

机构地区：[1]上海大学材料科学与工程学院,上海200444

出　　处：《铸造》2020年第1期16-22,共7页Foundry

摘　　要：运用扫描电子显微镜,X射线衍射仪和室温拉伸试验机等设备对重载车用低碳低合金铸钢的显微组织、碳化物及力学性能进行研究。结果表明:添加Nb元素,试验钢会出现明显的细晶强化现象,且随着Nb含量增加,试验钢中发生M3C型((Fe,Cr)3C)碳化物向MC型(NbC)碳化物的转变;当Nb添加过多时,则会出现碳化物以非连续链状形式沿晶析出的现象,从而使钢的力学性能下降。Nb的添加量在0.2%左右时,该铸钢材料表现出良好的微观组织和力学性能。The microstructure, carbide and mechanical properties of low carbon low alloy cast steel for heavy duty vehicles were studied by means of scanning electron microscopy, X-ray diffractometer and room temperature tensile testing machine. The results show that the addition of Nb element can result in obvious fine-grained strengthening, and with an increase in Nb content, the transformation of M3 C type((Fe,Cr)3 C) carbide into MC type(NbC) carbide occurs in the experimental steel. When Nb is excessively added, there exist a phenomenon in which carbides are precipitated in a discontinuous chain form, thereby deteriorating the mechanical properties of the steel. The results further found that the cast steel material has good microstructure and mechanical properties when the amount of Nb added is about 0.2%.

关 键 词：NB 低合金铸钢 碳化物 力学性能 

分 类 号：TG142.1[一般工业技术—材料科学与工程]