实现聚碳酸酯(PC)材料高品质焊接是拓展其工程应用的重要方向. 焊接件残余应力聚集的位置易产生变形、裂纹等缺陷，使用过程中进而会形成应力腐蚀，导致强度降低，缩短焊接件的使用寿命. 为了实现PC材料的高质量焊接，提出了以表面涂有碳黑的铜膜为激光吸收材料的透射焊接新方法，并探究了不同激光工艺参数(激光功率和焊接速度)对焊接性能、铜膜变形量及残余应力的影响规律. 结果表明，随着激光功率和焊接速度的增大，焊缝抗剪强度和铜膜变形量均先增大后减小；焊缝宽度与激光功率成正比，与焊接速度成反比；残余应力与激光功率成正比，与焊接速度成反比；且发现铜膜变形在一定程度上有利于提高焊接性能和减小残余应力.
Achieving high-quality welding of polycarbonate (PC) materials is an important direction for expanding its engineering applications. The location where the residual stress of the welded parts accumulates is prone to deformation, cracks and other defects. During use, stress corrosion will be formed, which will reduce the strength and shorten the service life of the welded parts. In order to achieve high-quality welding of PC materials, a new method of transmission welding using a copper film coated with carbon black as the laser absorbing material was proposed, and the influence of different laser process parameters (laser power and welding speed) on welding performance, copper film deformation and residual stress was explored. The results show that: with the increase of laser power and welding speed, the shear strength of weld and copper film deformation first increase and then decrease; the width of the weld is proportional to the laser power Proportional and inversely proportional to the welding speed; the residual stress is proportional to the laser power and inversely proportional to the welding speed; and it is found that the deformation of the copper film is beneficial to improve the welding performance and reduce the residual stress to a certain extent.
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