采用YAG激光透射焊接聚甲基丙烯酸甲酯(PMMA)板材,对其工艺、焊接区形貌和拉伸性能进行了研究。结果表明:在未添加吸光剂条件下,激光功率高于200W时,透明和黑色PMMA板激光透射焊接性能良好,上层透明PMMA材料的激光入射面无烧蚀损伤,拉伸试验中透明PMMA板断开,焊接区无开裂,最大载荷为2110N。激光功率低于200W时,单道焊接条件下焊接区被拉开,最大载荷1170N。透明PMMA板和其他颜色PMMA板在焊接时,需要添加吸光剂。采用黑色热塑性丙烯酸树脂为吸光剂的条件下,焊接效果较好。
Experiments on YAG laser transmission welding of polymethylmethacrylate(PMMA) specimens are carried out to study laser welding technology,microstructure of welding zone and tensile property.The results show that transparent and black PMMA specimens can be well welded and there is no ablated mark at laser irradiated surface without optical absorbing material when laser power is above 200 W.In tensile experiments,the transparent PMMA specimens break at the edge of welding zone with the maximum load of 2110 N,and there is no crack at the welding zone.When laser power is below 200 W,the welding zone is fractured under the condition of single track welding,and the maximum load is 1170 N.Optical absorbing material can be used to improve the reliability of laser transmission welding of transparent and color PMMA specimens.The quality of laser transmission welding with black thermoplastic acrylic resin is better than that of other absorbing materials.