Resistant supotsuto welding process null of the resin sandoitsuchi die laminate and usually

摘要

PURPOSE:To increase the joining strength in welding and reduce the cost by performing a spot welding by setting the contact area of the electrode of a sandwich type resin laminated plate side smaller than the contact area of the electrode of an ordinary steel plate side. CONSTITUTION:In case of a sandwich type resin laminated plate 11 and ordinary steel plate being subjected to a resistance spot welding, the contact area of the electrode 13 of a laminated plate 11 side and the laminated plate 11 is set about 9-25% smaller than the contact area of the electrode 14 of the steel plate 2 side and steel plate 2. The current density of the laminated plate 11 side is relatively increased and the colorific value is also increased moreover, the quantity of heat escaped by the heat transfer is reduced. The nugget formation at the welding time is therefore moved to the laminated plate 11 side at its center and the nugget 15 is formed at both parts between the laminated plate 11, steel plate 12 and between the front and back metal plates 11a, 11c of the laminated plate 11. In this way, the joining strength in welding is improved and the welding cost is reduced as well.