Effects of Cr and Zr on Interface Microstructures and Properties of CuW/CuCr Integral Materials

Abstract:

CuW/CuCr integral materials with Cu-Cr-Zr powder interlayer was prepared by integral sintering infiltration method. The effects of Cr and Zr content and solution aging heat treatment on the microstructure and properties of the interface and both sides of the material were studied. The results show that with the increase in Zr content in Cu-15%Cr-x%Zr (mass fraction, similarly hereinafter) interlayer, the eutectic phase amount on CuCr side of the integral material increases, and the conductivity at CuCr end decreases. The hardness increases first and then decreases. At the same time, the addition of Zr promotes the diffusion of Cr into W. The tensile test bars of integral materials with different interlayers were prepared, and the interfacial tensile strength was tested and the fracture morphology was analyzed. It is found that when the Zr content in the interlayer is 0.5%, the interfacial tensile strength of the whole material reaches the maximum value of 517 MPa, which is 18% higher than that of the CuW/CuCr integral material with Cu-15%Cr interlayer without Zr. The tearing edge of Cu phase in the tensile fracture becomes shallower and shorter, and the number of cleavage fractures of W particles increases, which indicates that the interfacial strength of Cu/W phase and the end strength of CuCr are improved.

Key words:CuW/CuCr integral material;interfacial microstructure;solution and aging treatment;fracture morphology;interface bonding strength