Abstract
Commercial aluminium plates are welded by means of the lap-type cold pressure welding, and the effects of the welding load, the figure of merit, the thickness and width of the welded plate, and the diameter of punch on the breaking strength of welded joints are studied experimentally. The main results obtained are as follows:
(1) The perfectly welded joint cannot be obtained until the welding pressure exceeds a certain value, and the breaking strength of perfectly welded joints does not increase by a greater pressure than this value.
(2) To obtain a fully welded joint, the figure of merit must be smaller than 40%.
(3) The maximum breaking strength of the lap welded joint increases with increasing plate thickness, but the joint efficiency and the minimum pressure for perfect welding are nearly constant regardless of the plate thickness.
(4) There are two types in the fracturing of flat welded joints. One takes place when the plate width is not sufficient compared with the diameter of punch, and the other occurs in the case of a sufficient plate width. In the latter case, the breaking strength is constant regardless of the plate width.
