一种Nb-V复合微合金化非调质钢的组织和性能

Microstructure and Mechanical Properties of a Kind of Nb-V Micro-alloyed Forging Steel

利用光学显微镜、透射电镜及力学性能测试等手段,研究了一种低碳Nb-V复合微合金化非调质钢的组织与性能.结果表明,成分为0.24%C-1.99%Mn-0.30%Si-0.51%Cr-0.08%V-0.07%Nb的非调质钢,在加热制度为1 200℃×1 h时锻造后空冷或风冷,可以获得较好的综合性能,其原因是Nb-V复合微合金化可以有效地细化非调质钢的组织,因而其冲击韧性得到提高.进一步分析表明,这种钢能够满足汽车前轴的使用要求,可以用于重卡前轴的设计和制造.

By means of optical microscopy, TEM and testing of mechanical properties, the microstructure and mechanical properties of a kind of Nb-V micro-alloyed forging steel was investigated. The results showed that it is a 0.24 % C-1.99 % Mn-0.30 % Si-0.51% Cr-0.08 % V- 0.07 % Nb steel that doesn＇ t belong to tempered-hardened steel and has a better comprehensive performance after forging at 1 200℃ for lhr with then air- or wind-cooled. The reason why it is improved is that the Nb-V micro-alloying process can effectively refine the microstructure of the steel, thus improving its impact toughness. The further analysis showed that this steel can be used to meet the demands for designing and manufacturing the front axle of heavy-duty trucks.