Pulsed Electric Current Bonding of Tungsten to Copper with Intermediate Layer

Abstract

Pulsed electric current sintering (PECS) was applied to the bonding of W (tungsten) to Cu (copper) using Nb or Ni powder as an intermediate layer. The influence of the intermediate layer on the bond strength of the joint was investigated by observation of the microstructure. The bonding process was carried out at carbon-die temperatures of 1073 and 1173 K for 1.8 ks at a bonding pressure of 130 MPa. The bond strength of the joint with an intermediate layer of Ni powder was 250 MPa. This joint fractured in the Cu base during the tensile test. SEM observations of the joint with an intermediate layer of Ni revealed that a diffusion layer formed at the joint interface.