Electron beam welding - high silica aluminium welding

Electron beam welding - high silica aluminium welding

Last time we introduced you to laser welding as a solution to the challenge of welding high silica aluminium. The solution to the challenge of welding high silica aluminium also includes electron beam welding. We continue today with this welding method.

Electron beam welding is a welding method that uses high speed electrons generated by a high electric field, which are focused to form a stream of electrons that strike the welded part of the metal to be welded, converting its power into heat and causing the welded metal to fuse. Electron beam flow has high energy density, strong penetration ability, large weld depth to width ratio, fast welding speed, small input energy, so the heat affected zone is small and welding deformation is small. Therefore, the electron beam welding quality is good and the mechanical properties of the weld are high. Shi Lei et al. extruded cast AlSi12CuMgNi aluminium alloy piston top ring and forged piston skirt for vacuum electron beam welding, the microstructure and mechanical properties of the welded joint under optimized process conditions were studied. The results show that the joint is well formed, no obvious heat-affected zone, narrow weld; weld area is mainly composed of fine α-Al phase, α + Si eutectic, primary silicon and Mg2Si and other strengthening phases; weld centre organization for fine equiaxed crystals and dendrites; fusion zone organization is mainly columnar crystal. The strength of the joint is not lower than that of the extrusion casting base material, and the hardness of the weld is higher than that of the base material; the tensile fracture section of the welded joint is distributed with a large number of tearing ribs and dissociation surfaces, and is brittle fracture.