钒、铬微合金化对高碳钢微观组织与力学性能的影响

Effects of Micro-alloying of Chromium and Vanadium on Microstructure and Mechanical Properties of High Carbon Steel

为了开发性能更优的高碳盘条钢,在原有70钢的基础上,以铬、钒微合金化设计开发新钢种,并分析了铬、钒对试验钢的微观组织和力学性能的影响。铬、钒单独微合金化,使索氏体化率增大、片层间距减小、原始奥氏体晶粒细化;与70钢相比,随铬、钒含量的增加,钢的抗拉强度逐渐升高,断口伸长量下降。铬钒复合微合金化对钢中微观组织的改善明显好于单独微合金化;与70钢相比,铬钒复合微合金化钢的强度显著升高,塑性略有降低;与80钢相比,铬钒复合微合金化钢的强度和塑性均较高。

In order to develop a high-carbon steel wire rod with better performance, new steels were designed and developed using chromium and/or vanadium micro-alloying method on the basis of the primary 70 steel. In addition, the influences of chromium and/or vanadium on microstructure and mechanical properties of the experimental steels were analyzed. After chromium and vanadium micro-alloying separately, the volume fraction of sorbite increased, lamellar space decreased, and the original austenite grain refined. Compared to 70 steel, chromium content and vanadium content increased, the tensile strength of the steels gradually improved and the corresponding elongation decreased. Complex micro-alloying of chromium and vanadium obviously optimized the mi- crostructure of the steel, and the optimization effect is significantly better than individual micro-alloying of chromium and vanadium. By contrast with 70 steel, the strength of the steel produced by complex micro-alloying of chromium and vanadium notably increased and the plasticity decreased slightly. By comparison with 80 steel, the strength and plasticity of the steel prepared by complex micro- alloying of chromium and vanadium increased.