Russian scientists of the Kovrov State Technology Academy have proposed a new technology for aluminium alloy welding based on using of two lasers. The first laser removes the oxide film by small portions from the surface of welded components, and the second laser executes the welding. Although the first phase lasts for about one millionth of a second, it is very important, since the refractory oxide film deteriorates the welding strength. The new method is also characterized by one more benefit: the place the juncture is covered with a thin film of molten metal increasing the efficiency of laser beam. The film also retains tiny particles, which erupt from the metal in the course of welding and increases the maximal welding depth.
The new laser device consists of two modified lasers, the mirror system and the lens, which focuses the emission on the welding area. The radius of laser beam which performs welding makes 0.3 millimeters. The welding rate was equal to 30 millimeters per minute.
The scientists have experimentally compared the new welding technology with the common one, where only one laser is used. The experiments have proved that a new method provides for twice or thrice higher depth of welding. In addition, the quality of seams (judging by the so-called porosity of weld) increases twice, thus improving the product strength.
Mr. Andrey Siver | alfa
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