Effect of the Regimes of Machining Butting Edges on the Quality of Permanent Joints Made by Fusion Welding when Assembling Aircraft Titanium Structures

The article presents the results of the study of the effect of machining on the quality of permanent joints made by fusion welding. The effects of various types of machining (high-speed milling, cutting with guillotine shears, grinding) on the level of defectiveness of permanent joints made by automatic argon-arc and electron-beam welding have been determined. It was found that it is incorrect to assess the quality of machining butting edges for welding by the roughness parameter. The most acceptable parameter is the saturation by capillary-condensed moisture. It is shown that the thermal processes occurring during high-speed milling in the near-surface and surface layers, regardless of the roughness, lead not only to the minimum saturation parameter of capillary-condensed moisture (from 1.12 to 2.18), but also to dehydrogenization in the surface layer of the butting edges of future permanent joints. The obtained results of the research can be applied in technological processes of production of aircraft large load-bearing elements performed by welding.

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