The automatic degree of laser welding machine is very simple with high welding process. Non-contact operation method can meet the requirements of clean and environmental protection. The use of laser welding machine workpiece can improve work efficiency, finished workpiece appearance, weld small, welding depth, welding quality is high. Laser welding machine is widely used in the processing of dental denture, keyboard welding, steel welding, sensor welding, battery sealing cover welding and so on. However, the cost of laser welding machine is higher, the accuracy of workpiece assembly is higher, and there are still limitations in these aspects.
Before the 20 world 70, the High Power Continuous waveform (CW) lasers had not been developed, so the research focused on pulsed laser welding (PW). Most of the early laser welding experiments were based on the Ruby Pulse laser, the typical peak output power of 1ms pulse is about 5KW, the pulse energy is 1~5j, and the pulse frequency is less than 1 Hz. The average output power of these lasers was quite low, although the high pulse energy was able to live, which was mainly determined by the low efficiency of the lasers and the stimulated properties of the luminous matter. Because of its high average power, the laser becomes the preferred equipment for spot welding and seam welding after its appearance, and its welding process is carried out through solder joints, until the birth of the continuous power waveform laser with a real meaning after 1KW is realized by laser seam welding.