摘要
以V单一合金化和Cu-V双合金化的锰合金钢为研究对象,对比2种锰钢在低温回火和时效处理前后的力学性能变化。研究发现,2种钢淬火后经100~175℃回火后,屈服强度因淬火残余应力的释放而提高,并趋于稳定;550℃时效后Cu-V钢中析出的VC颗粒尺寸大于V钢,但数量密度更低,推测是因为富Cu相和VC粒子均在位错、晶界等形核位点独立析出。因此,Cu-V钢中VC在更少的位点上形核,然后长大至更大尺寸。基于2种钢时效后实测的屈服强度增量及时效前后的变化值(残余应力、位错强化、固溶强化、晶粒细化强化等),定量估算出V钢和Cu-V钢的实际时效析出强化值。研究结果表明,Cu-V钢的Cu、VC双析出强化显著高于V钢的VC单一强化贡献,且后者双析出强化的叠加符合均方根叠加模型。这是由于2种粒子尺寸相近且均以绕过机制强化,而经典Ashby位错绕过强化理论认为此时可将两者简化为同一种粒子的析出强化。
Taking mere addition of V and dual additions of Cu-V into Mn-alloyed steel as the research object,the mechanical properties of the two Mn-alloyed steels before and after low temperature tempering and aging treatment were compared.It is found that the yield strength of the two steels increases and tends to be stable due to the release of quenching residual stress after quenching and tempering at 100-175℃.After aging at 550℃,the size of VC particles precipitated in Cu-V steel is larger than that in V steel,but the number density is lower.It is speculated that both Cu-rich phase and VC particles are precipitated independently at nucleation sites such as dislocations and grain boundaries.Therefore,VC in Cu-V steel nucleates at fewer sites and then grows to a larger size.The actual aging precipitation strengthening values of V steel and Cu-V steel were quantitatively estimated based on the measured yield strength increment and the two steels before and after aging(residual stress,dislocation strengthening,solid solution strengthening and grain refinement strengthening).The results show that the double precipitation strengthening of Cu and VC in the latter is significantly higher than the single strengthening contribution of VC in the former,and the superposition of the double precipitation strengthening of the latter conforms to the root mean square superposition model.This is because the two kinds of particles are similar in size and both are strengthened by bypass mechanism,while the classical Ashby dislocation bypass strengthening theory believes that both can be simplified as the precipitation strengthening of the same kind of particles.
作者
晁思佳
丁方林
赖伟强
胡斌
罗海文
CHAO Sijia;DING Fanglin;LAI Weiqiang;HU Bin;LUO Haiwen(School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beijing 100083,China)
出处
《中国冶金》
北大核心
2025年第10期27-36,共10页
China Metallurgy
基金
中国宝武低碳冶金创新基金资助项目(BWLCF202213)
云南省重点研发计划资助项目(202403AA080013)。
关键词
铜析出
碳化物
时效
析出强化
强化叠加机制
Cu precipitate
carbide
aging
precipitation strengthening
superposition mechanism of strengthening
