激光浸液诱导冲击调控电火花线切割热变形行为  

Regulation of Thermal Deformation Behavior in Wire EDM Process Based on Underwater Laser-induced Shockwave

作　　者：邱文哲 张臻 王鹏 刘邓华 魏世川 张国军[3] QIU Wenzhe;ZHANG Zhen;WANG Peng;LIU Denghua;WEI Shichuan;ZHANG Guojun(School of Aerospace Engineering,Huazhong University of Science and Technology,Wuhan 430074;School of Mechanical Engineering and Automation,Northeastern University,Shenyang 110819;School of Mechanical Science&Engineering,Huazhong University of Science and Technology,Wuhan 430074)

机构地区：[1]华中科技大学航空航天学院,武汉430074 [2]东北大学机械工程与自动化学院,沈阳110819 [3]华中科技大学机械科学与工程学院,武汉430074

出　　处：《机械工程学报》2024年第9期273-285,共13页Journal of Mechanical Engineering

基　　金：国家自然科学基金(51705171,51975228);广东省基础与应用基础研究基金(2022A1515140083);中国空气动力研究与发展中心结冰与防除冰重点实验室开放课题(LADL20220411)资助项目。

摘　　要：电火花线切割(WEDM)加工金属薄壁过程中产生的热变形现象几乎无法避免,制约了WEDM在薄壁类零件精密加工中的应用。本研究提出一种利用激光浸液诱导冲击调控WEDM加工金属薄壁热弯曲变形的新工艺,以获得低/无变形薄壁件。对不同线切割参数加工的In718与TC4金属薄壁热变形量进行标定,获得热弯曲量与工艺参数间的规律。薄壁热弯受脉冲时间影响最为明显,脉冲间隙的影响则并不显著。基于激光冲击仿真与实验结果选取合适的激光参数对薄壁区域进行冲击加工,能够有效恢复薄壁热变形。针对不同厚度的In718与TC4薄壁,均能使用激光浸液诱导冲击对热弯曲变形量进行调控,当激光能量为80 mJ,光斑间距(x-y)为0.5~0.5 mm,冲击次数为1时,调控效果最好。调控后的所有薄壁翘曲度最低仅1.4μm,热变形最高可减少98.35%。对加工后的薄壁表面完整性进行检测,结果表明新工艺在调控薄壁变形的同时,薄壁表面硬度提高了20%以上,降低表面粗糙度与重铸层厚度,此外还能一定程度改善薄壁表面裂纹。The thermal deformation during wire electric discharge cutting(WEDM)processing of thin-walled metals is almost unavoidable,which restricts the application of WEDM in precision machining of thin-walled parts.In this study,a new process of underwater laser-induced shockwave to regulate the bending deformation of thin-wall metal induced by WEDM are proposed,which can obtain low/no deformation thin-wall parts.The thermal deformation of In718 and TC4 thin walls processed with different wire-cutting parameters is calibrated,and the relationship between the thermal and wire-cutting process parameters is obtained.The influence of thin walls'thermal deformation is most obviously affected by pulse time,while the effect of pulse gap is not significant.Based on the results of laser shock simulation and experiment results,the thermal deformation of thin walls can be effectively recovered by selecting suitable laser parameters for impact processing of thin walls.For In718 and TC4 thin walls of different thicknesses,the thermal deformation can be controlled by underwater laser-induced shockwave.When the laser energy is 80 mJ,the spot distance(x−y)is 0.5-0.5 mm,and the number of impacts is 1,the control effect achieves the best.The lowest warpage of all thin walls after regulation is only 1.4μm,and the thermal deformation can be reduced by up to 98.35%.By testing the surface integrity of the processed thin walls,the results show that this new process can improve the surface hardness of the thin wall by more than 20%,reduce the surface roughness and the thickness of the recast layer,and improve the surface cracks to some extent.

关 键 词：激光诱导冲击 电火花线切割 变形恢复 金属薄壁 

分 类 号：V261[航空宇航科学与技术—航空宇航制造工程]