电流脉冲对45碳钢试样位错密度和残余应力的影响

发布时间：2018-03-18 01:34

本文选题：位错密度　切入点：残余应力　出处：《材料热处理学报》2015年S1期 　论文类型：期刊论文

【摘要】：研究了电流脉冲对淬火45碳钢试样位错密度和表面残余应力的影响。根据XRD图谱,采用Modified Williamson-Hall(MWH)方法计算位错密度,进一步结合微观组织结构,分析了位错密度和残余应力的关系。结果表明,电流脉冲处理前后,位错密度由1.21×1015m-2变为0.80×1015m-2,表面残余应力σx由-250 MPa降低到-142 MPa,σy由-363 MPa降低到-172 MPa。与热处理相比,电流脉冲处理的试样位错密度和残余应力的降低率都比较大,表明电流脉冲除了产生热作用外,还产生了非热作用。位错密度和残余应力存在一定关系,符合Kocks-Mecking模型。电流脉冲处理过程中,位错激活运动,导致位错湮灭,位错密度降低,是残余应力降低的主要因素。
[Abstract]:The effect of current pulse on dislocation density and surface residual stress of quenched 45 carbon steel samples was studied. According to XRD diagram, dislocation density was calculated by Modified Williamson-Hallan MWHs method, and the microstructure was further combined. The relationship between dislocation density and residual stress is analyzed. The results show that the dislocation density changes from 1.21 脳 1015m-2 to 0.80 脳 1015m-2, the surface residual stress 蟽 x decreases from -250 MPa to -142MPa, and 蟽 y decreases from -363 MPa to -172MPa. The dislocation density and residual stress of the sample treated by current pulse are both large, which indicates that the current pulse not only produces thermal action, but also produces non-thermal action. There is a certain relationship between dislocation density and residual stress. In accordance with the Kocks-Mecking model, dislocation activates during current pulse processing, which leads to dislocation annihilation and dislocation density decrease, which is the main factor for the reduction of residual stress.
【作者单位】：浙江省先进制造技术重点研究实验室浙江大学流体动力与机电系统国家重点实验室;
【基金】：航空科学基金(20140876003) 国家自然科学基金(50675200);国家自然科学基金创新研究群体科学基金(51221004)
【分类号】：TG142.15

【参考文献】