圆振荡激光束提高激光弯曲成形效率  

Improving the efficiency of laser bending forming using circularly oscillating laser beam

作　　者：沈宗宝[1] 韩曜阳 孟康楠 李品[1] SHEN Zongbao;HAN Yaoyang;MENG Kangnan;LI Pin(School of Mechanical Engineering,Jiangsu University,Zhenjiang 212013,China)

机构地区：[1]江苏大学机械工程学院,江苏镇江212013

出　　处：《光学精密工程》2024年第6期806-821,共16页Optics and Precision Engineering

基　　金：中国博士后科学基金(No.2019M651724)。

摘　　要：激光弯曲成形技术常用的激光类型是点激光,在温度梯度机理的作用下单次成形角度有上限,在3°左右。为了增大点激光单次成形角度,提高成形效率,本文以不锈钢304板为对象,通过试验对比探索了将圆振荡模式应用于激光弯曲成形中以提高弯曲角方法的可行性;并且借助于三维视觉传感器测量板件在圆振荡激光束弯曲成形过程中的动态响应,从余热效应、吸收率等角度分析其弯曲成形机理。对比试验结果显示,在激光能量密度较高的情况下,圆振荡模式确实可以明显提高工件的弯曲角,增长率在60%左右。同时,三维视觉传感器的测量结果显示出了板件在成形过程中的复杂形变与角度变化过程:板件在长度与宽度方向上均产生了塑性变形,长宽形变比约为10∶1;单次扫描成形板件弯曲角增长过程呈现不同的增长曲线;多次扫描成形弯曲角分布不均衡。此外,板件厚度也逐渐增加,热影响区微观晶粒得到细化。为进一步理解圆振荡激光束弯曲成形过程与机理提供了试验支撑。Laser bending forming techniques commonly utilize point lasers,which have a limited maxi⁃mum bending angle of approximately 3°due to the temperature gradient mechanism.To increase the bend⁃ing angle and improve the forming efficiency of point laser bending,this study explored the feasibility of ap⁃plying the circular oscillation mode to enhance the bending angle in the bending process of stainless steel 304 sheets.Additionally,the dynamic response of the workpiece during circular oscillation laser bending forming was measured using a three-dimensional vision sensor to investigate the bending deformation mechanism from the perspective of thermal effect,variation in absorption,etc.The comparative experi⁃mental results show that the circular oscillation mode significantly improves the bending angle of the work⁃piece,with a growth rate of approximately 60%when the laser has a higher energy density.At the same time,the measurement results from the three-dimensional vision sensor reveal the complex deformation and angle changes of the workpiece during the forming process:plastic deformation occurs in both the length and width directions of the workpiece,with the length-width deformation ratio is about 10:1;the growth of the bending angle during a single scan exhibits different growth curves;and the distribution of bending angles in multiple scans is uneven.In addition,the thickness of the plate also gradually increases,and the micro-grains in the heat-affected zone are refined.These experimental findings provide support for a better understanding of the process and mechanism of circular oscillation laser bending forming.

关 键 词：激光弯曲成形 圆振荡激光束 不锈钢304 变形机理 

分 类 号：TG665[金属学及工艺—金属切削加工及机床]