透明和纯白热塑性塑料是激光透射焊接中最难焊接的两类塑料品种。为将透明聚对苯二甲酸乙二醇酯(PET)或纯白聚丙烯(PP)焊接在一起, 利用这两种塑料在2 μm波段具有适度透过率和吸收率的光学特性, 使用自主研发的2 μm光纤激光器在不添加任何吸收剂的情况下, 分别对这两种塑料进行搭接焊, 并将其与0.808 μm激光采用添加吸收剂方法的焊接效果进行对比。结果表明, 在无吸收剂的条件下, 2.0 μm激光可成功焊接透明PET和纯白PP, 其样品的破坏拉伸力分别达到母材的57.8%和93.3%, 且相对于0.808 μm激光的焊接效果, 2.0 μm激光焊接得到的样品的力学性能较佳, 外观较清洁、美观。

The welds of transparent and pure white thermoplastics are the most difficult species in plastic transmission laser welding. Using the optical characteristics of moderate transmittance and absorptivity in the 2 μm band to weld transparent polyethylene terephthalate(PET)or pure white polypropylene(PP)together, two kinds of plastics were lap-welded without adding any absorbent with the self-developed 2.0 μm fiber laser, and compared with the welding effect of the 0.808 μm laser using the additive absorbent method. The results show that the weld of transparent PET and pure white PP by 2 μm laser without any absorbent are feasible. The tensile strength of the samples reaches 57.8% and 93.3% of the base material respectively. Compared with the welding effect of 0.808 μm laser, the samples obtained by 2.0 μm laser welding are cleaner and more aesthetic with better mechanical properties.