Welding methods: Almost all kinds of welding methods can be used to weld aluminum and aluminum alloy, but aluminum and aluminum alloy for a variety of welding methods, the adaptability of various welding methods have their respective applications. Welding gas and welding electrode arc welding method, simple equipment, easy to operate. Gas welding can be used to weld the aluminum sheet and castings with low requirements for welding quality. Electrode arc welding can be used for welding of aluminum alloy castings. Inert Gas shielded arc welding (TIG or MIG) method is the most widely used aluminum and aluminum alloy welding method. Aluminum and aluminum alloy sheet can be tungsten electrode AC argon arc welding or tungsten pulse argon arc welding. Aluminum and aluminum alloy thick plate can be used tungsten-helium arc welding, argon-helium mixed tungsten gas shielded welding, melting electrode gas shielded welding, pulse melting electrode gas shielded welding. The melting pole gas shielded welding, pulsed-melting electrode gas shielded welding application is more and more extensive (argon or argon/helium mixture) before welding.