摘要
对比研究了金刚石刀具和硬质合金刀具镜像铣,以及化学铣切2A12-T4铝合金试样的表面形貌、表面粗糙度、残余应力、硬度和疲劳性能。结果表明:镜像铣等厚度平板试样(一面硬质合金刀具加工,一面金刚石刀具加工)的细节疲劳额定强度比化学铣切试样提高了4.27%,而金刚石刀具镜像铣下陷试样的细节疲劳额定强度则提高了22.46%;金刚石刀具镜像铣试样获得了比硬质合金刀具镜像铣试样以及化学铣切试样更高的疲劳抗力。金刚石刀具镜像铣在试样表面引入了残余压应力,提高了表面硬度,降低了表面粗糙度,并未使表层组织受到破坏,因此裂纹萌生和扩展阻力提高。化学铣切试样表面存在的点蚀坑、晶间腐蚀缺陷及残余拉应力,以及硬质合金刀具镜像铣试样表面存在的较深刀痕沟槽和残余拉应力均促进了裂纹的萌生。
The surface morphology,surface roughness,residual stress,hardness and fatigue properties of 2A12-T4aluminum alloy samples processed by diamond tool and carbide tool mirror milling and chemical milling were studied by contrast.The results show that comparing with that of chemical milled samples,the detailed fatigue rated strength of carbide tool mirror milled equal thickness flat sample(one side for carbide tool processing and the other side for diamond tool processing)was improved by4.27%,while that of diamond tool mirror milled depression sample was improved by22.46%.Thefatigue resistance of diamond tool mirror milled sample was higher than that of carbide tool mirror milled and chemical milled samples.The diamond tool mirror milling introduced residual compressive stress on the sample surface,improved the surface hardness,decreased the surface roughness,and did not damage the surface structure,resulting in increase of crack initiation and propagation resistance.The pits,intergranular corrosion defect and residual tensile stress on chemical milled sample surface,and deep tool grooving and residual tensile stress on carbide tool mirror milled sample surface all promoted the initiation of cracks.
作者
史建猛
张海宝
张月玲
贾天一
王新磊
陈奕志
刘道新
SHI Jianmeng;ZHANG Haibao;ZHANG Yueling;JIA Tianyi;WANG Xinlei;CHEN Yizhi;LIU Daoxin(AVIC Xi′an Aircraft Industry Group Company Ltd.,Xi′an 710089,China;College of Civil Aviation,Northwestern Polytechnical University,Xi′an 710072,China)
出处
《机械工程材料》
CAS
CSCD
北大核心
2023年第7期14-21,30,共9页
Materials For Mechanical Engineering
基金
国家自然科学基金资助项目(52271071)
国家重大科技项目(J2019-I-0016-0015)。
