Aluminum alloy thin plate welding method and aluminum alloy thin plate welding device

The invention provides an aluminum alloy thin plate welding method and an aluminum alloy thin plate welding device. The aluminum alloy thin plate welding method and the aluminum alloy thin plate welding device are easy to use and are slightly influenced by welding space. The method includes the steps that high-temperature metal with strength unrecovered after welding is rolled to compensate compression plastic strain generated in the heating process, so that the shrinkage amount of weld joints is reduced, transient stress in the welding process is lowered, and then transient welding deformation is reduced; the metal which is rolled and is still in a cooling shrinkage and stretched state is extruded, under the action of extrusion force, a part of tensile stress is offset, and workpieces are protected against hot cracks. The aluminum alloy thin plate welding device comprises a trolley frame, a TIG welding device, a plate pressing device, a rolling device, an extrusion device and a control system, wherein the TI