Microstructural evolution and properties of CuW/CuCr interface infiltrated with CuCrNixTiZr multi-component powder interlayers

Abstract

CuW/CuCr integral materials were prepared by infiltration diffusion technology, and the multi-component powders with high entropy effect were used as the interlayer. The effects of CuCrNixTiZr high entropy alloy interlayers on the interfacial microstructures and properties of CuW/CuCr were studied. The results show that the interlayers with 0.5 mm thickness generate high entropy effect during infiltration for 1.5 h at 1350 °C, forms a simple solid solution phase at the CuW biphase interface and no intermetallic compounds were formed in the CuW/CuCr interface. EDS and XRD analysis show that metallurgical diffusion and melting occur at the CuW/CuCr interface in the interlayer infiltration diffusion process, which makes the Cu and W phase form metallurgical bonding at the Cu/W interface. With the increase of Ni content, the hardness of CuCr side of the integral material first increased and decreased, and the maximum hardness increases by 23.6 %. When the interlayer is CuCrNi2TiZr, the maximum interface bonding strength is 492 MPa, which is 50 % higher than that of the integral material without interlayer. The fracture morphology is mainly composed of the network structure generated by the ductile tearing of Cu phase and W cleavage fracture, and the cleavage fracture leave river pattern on the W particles.