钒、磷对中碳非调质钢组织和力学性能的影响

Effect of Vanadium and Phosphorus on Microstructures and Mechanical Properties of Medium-Carbon Non-Quenched and Tempered Steel

采用扫描电镜、透射电镜、原位纳米力学测试系统、能谱分析和断口检验研究了一种改变了机和磷含量的40MnV钢的显微观组织和力学性能,以揭示机和磷对中碳非调质钢的组织和性能的影响。研究结果表明:机和磷对中碳非调质钢均有明显的强化作用。其强化机制为:机的碳化物和氮化物的析出强化,磷的铁素体固溶强化,以及机和磷抑制先共析铁素体生成,从而增加珠光体含量所产生的复合强化。此外,机和磷还能适当促进中碳非调质钢再结晶时的晶粒长大。

Microstructures and mechanical properties of a type of 40 MnV steel in which vanadium and phosphorus contents were changed were investigated by means of scanning electron microscope, transmission electron microscope, optic microscope, in-situ nanomechanical test system, energy dispersive spectrdmeter, and fracture testing for the purpose of discovering the effect of vanadium and phosphorus on structures and properties of mediumcarbon non-quenched and tempered steel. The results show that both vanadium and phosphorus may render the strengths of the medium-carbon non-quenched and tempered steel much higher. The mechanism whereby the steel is strengthened by vanadium and phosphorus is precipitation strengthening of carbide and nitride of vanadium,solution strengthening of phosphorus in ferrite, and their complex strengthening that stems from pro-eutectoid ferrite formation being inhibited thereby increasing amount of pearlite. In addition, vanadium and phosphorus can promote grain growth in the medium-carbon non-quenched and tempered steel during recrystallization to a certain extent.