Patent ID: 9289842
Filing Date: 2016-03-22
CPC Classification: B23K,B32B,Y10T

Claim Text:
1. A method of bonding a first metallic workpiece and a second metallic workpiece having different melting points and thermal conductivities, the method comprising: applying a first coating to at least a portion of the first metallic workpiece, the first coating being made of a material having a lower melting point than the material of the first metallic workpiece; applying a second coating to the first metallic workpiece at substantially the same location as the first coating, prior to applying the first coating, wherein the second coating is made of a material having a higher melting point than the material of the first metallic workpiece; positioning the first metallic workpiece and the second metallic workpiece with respect to each other to form at least one joint where the first and second metallic workpieces are to be bonded; and welding the first metallic workpiece to the second metallic workpiece along the at least one joint via an arc welding process including a welding wire such that the first metallic workpiece is wetted and brazed, and the second metallic workpiece is melted and fused along the at least one joint; and wherein the arc welding process involves a cyclic alternating of a first stage, in which an electric current is supplied to the welding wire as the welding wire is moved toward the first and second metallic workpieces, and a second stage, in which the electric current is reduced and the welding wire is moved away from the first and second metallic workpieces, to generate and detach a plurality of molten droplets along the at least one joint, the molten droplets being formed from the welding wire in the first stage.