Microstructure and properties of CuCr contact materials with different Cr content

In order to study effect of Cr content on microstructure and properties of CuCr contact material, three different Cr content contact materials, named CuCr25, CuCr30 and CuCr40, were manufactured by vacuum casting process. The microstructure, physical properties and breaking current properties were studied. The results show that both the consistency of the microstructure and the tensile strength increase, while the Cr particle size, the electrical conductivity and the density all decrease with increasing Cr content. The interrupting property of CuCr25 and CuCr30 is almost the same, whereas that of CuCr40 is the worst.