The process parameters of laser welding are more difficult to master, because the thermal efficiency has great fluctuations during the welding process, and the surface condition of the titanium alloy rod to be welded has a great influence on the thermal efficiency: the surface brightness has a greater impact, the brighter the surface, the laser The greater the light emission, most of the laser energy is reflected onto other objects and transmitted to the surrounding material or medium in the form of “heat”. But the thermal efficiency will change suddenly. Before the titanium alloy rod melts, only about 10%-20% of the light energy is absorbed by the titanium alloy rod and heats the titanium alloy rod. When the temperature rises to the melting point of the weld metal and begins to melt, the light absorption rate of the titanium alloy rod increases sharply. At this time, about 60%-80% of the light capacity is absorbed by the metal, and the sudden change of the thermal effect is very likely to cause the weld to burn. wear.
In order to avoid or reduce such adverse effects, some corresponding measures can be taken, such as roughening the surface of the titanium alloy rod to be welded; using a pulsed laser beam; adjusting the input energy; adjusting the spot size; changing the pulse width and the steepness of the attenuation wave, etc. .
Using a ruby ​​natural crystal containing alumina and dissolved with a low concentration of chromium atoms as the working substance of the laser generator, it is called a solid laser generator. Using CO2 as the working material of the laser generator is called the gas laser generator.
Recently, the power of laser welding machine is only at the level of kilowatts, and it is expensive, the welding cost is high, and the scope of application is not yet wide. It is only used for the welding points of some small parts in the production of certain instruments, especially some welding. When the position of the dot is relatively concealed, and it is impossible to apply welding by the general welding method. Multi-station welding can be realized by using laser beam and then using optical fiber and deflecting prism.