激光冲击强化7075铝合金数值模拟与试验分析  

Numerical Simulation and Experimental Analysis of Laser Impact on 7075 Aluminum Alloy

作　　者：朱烨[1] 胡斌 ZHU Ye;HU Bin(School of Mechanical and Automotive Engineering,Chuzhou Polytechnic,Chuzhou 239000,China)

机构地区：[1]滁州职业技术学院机械与汽车工程学院,安徽滁州239000

出　　处：《山东航空学院学报》2024年第4期60-66,共7页Journal of Binzhou University

基　　金：安徽高校自然科学重点项目(KJ2021A1411);滁州职业技术学院重点课题(YJZ-2020-05)。

摘　　要：针对激光冲击强化7075铝合金的问题,利用有限元技术和试验方法进行研究。首先利用光学显微镜、电子背散射衍射、显微硬度试验分析激光冲击前后试样上表面和横截面上微观组织和力学性能。其次采用有限元软件对7075铝合金进行数值模拟,得到应力变化云图和残余应力云图。试验结果表明,激光冲击细化表面和横截面晶粒组织,表面和横截面上再结晶晶粒占比分别从激光冲击前6.5%和8.3%提升到33.0%和80.1%;激光冲击后表面平均显微硬度提升幅度超过15%;随着深度增加,横截面上显微硬度提升幅度逐渐衰减。数值模拟结果表明,激光冲击过程中应力从447 MPa提升到581 MPa,在稳定时降到550 MPa;激光冲击提高了表面残余应力,而横截面上应力随着厚度增加而衰减。The problem of laser impact strengthening of 7075 aluminum alloy is investigated using finite element techniques and experimental methods.Firstly,the microstructure and mechanical properties of the upper surface and cross-section of the sample before and after laser shock are analyzed using optical microscopy,electron backscatter diffraction,and microhardness testing.Secondly,finite element software is used to numerically simulate 7075 aluminum alloy,obtaining stress variation cloud maps and residual stress cloud maps.The experimental results show that laser shock refines the surface and cross-sectional grain structure,and the proportion of recrystallized grains on the surface and cross-section increases respectively from 6.5%and 8.3%before laser shock to 33.0%and 80.1%,and the average microhardness increases on the surface after laser shock is over 15%.As the depth increases,the increase in microhardness on the cross-section decreases gradually.The numerical simulation results show that the stress increases from 447 MPa to 581 MPa during the laser shock process,and reduces to 550 MPa when stable.Laser shock increases the residual compressive stress on the surface,while the compressive stress on the cross-section decreases with increasing thickness.

关 键 词：激光冲击 7075铝合金 数值模拟 硬度 应力 

分 类 号：V252[一般工业技术—材料科学与工程]