Patent ID: 7654439
Filing Date: 2010-02-02
Classification: B21B,B23K

Abstract:
1. In a method of welding of metal plates in a solid phase, wherein the metal plates are combined to form a package, and welded together by heating and deforming the package by contacting the package with two rotating cylinders of different circumference, wherein a first cylinder has a radius R 1 and a second cylinders has a radius R 2 , the improvement comprising: providing a damping lining between the metal plates; placing the package between the first cylinder and the second cylinder such that the metal plate with the smallest yield value under welding temperature faces the cylinder with smaller diameter, heating and deforming the package in vacuum, and in two stages such that during the first stage the temperature reaches about 0.4 to about 0.5 of melting temperature of the metal plate with the smallest yield value, during the second stage the package is heated by a high frequency which heats the damping lining material up to about 0.92 to about 0.95 of its melting temperature, wherein angular velocities of the rotating cylinders and their radiuses are selected on the basis of the following formula: wherein σ ε H ω