In order to analyze the mechanical properties of laser transmission welding of polycarbonate, the transparent and opaque polycarbonates were welded by a 10 W diode end pumped solid state laser, respectively. The microstructure, fracture appearance, micro-hardness and tensile-shear strength of the welded joint were tested by optical metallographic microscope (OM), field emission scanning electron microscope (SEM), micro-hardness tester and electronic universal tensile machine, respectively. The results showed that the joint gradually become as similar adhesive joint from welded joint with the increase of laser power density. Layering and pores in the welded joint are the defects to resulting in poor mechanical properties. The mechanical properties of the welded joint can be improved by controlling laser power density. At the laser power density of 0.23 J/mm2, the tensile-shear stresses reaches 44 MPa, which is 68% of that of the basic materials. The micro-hardness on the center of the welded joint is very close to the basic material. The fracture is the mixture of ductile fracture and brittle fracture.

为研究聚碳酸酯激光透射焊接接头性能,采用10W半导体端抽运全固态（DPSS）激光器进行了聚碳酸酯材料的激光透射焊接。采用光学金相显微镜（OM）、场发射扫描电子显微镜（SEM）和电子万能实验拉力机分析了接头的显微形貌、断口形貌和拉伸剪切强度。结果表明,在激光功率8 W、激光频率50kHz、焊接速度350mm/s、激光扫描间距0.1mm时,试样的拉伸剪切强度达到44MPa,为母材强度的68%,焊缝内部的分层和气孔是影响接头力学性能和断裂机制的主要原因,通过激光塑料透射焊接技术,可以获得接头力学性能良好的焊接试样。

采用一级谐振两级放大的系统结构和激光单元分块设计方法,研制出了工业大功率脉冲固体激光器。在输出平均功率为957W连续运转2h后的功率不稳定度为2.5%,光电转换效率为3%,光束质量达到22mm.mrad,激光耦合进入0.6mm的光纤,放大级之后最高输出功率达到1125W。