The statement from the specialty literature which affirms that with the increasing of the diameter of the welded spot by cold pressure decreases the amount of resistance to shear force is due to reporting of the breaking by shear at the circular section of the point. Our experimental research shows that a welded cold joint in spots, correctly done, will be torn off near the weld spot by drawing the point from one of the tins. By reporting the force to the real section of breaking it resulted a constant stress resistance, no matter which the size of the welded point was. Therefore, the approximate theoretical calculation of the breaking force of a cold welded point, correctly executed, can be achieved by knowing the mechanical properties of the base metal. It has to be taken into consideration also the real section of the breaking point given by point's periphery and the thickness of the tin after deformation. The calculus is encompassing, due to cold hardening, the real mechanical characteristics are elevated.
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