MICROSTRUCTURE AND PROPERTIES OF CuCr25 ALLOYS WITH DIFFERENT Ni CONTENT

CuCr25 alloys containing different Ni content were prepared by vacuum induction melting (VIM). The micro structure and properties were tested. The results show that with the increase of Ni content in CuCr25 alloys, the Cr phase changed from developed dendrite into nodular grains and was drastically refined; the electrical conductivity significantly decrease, but still reach the level of conventional CuCr50 when the Ni content is below 0.5%. The Ni content had little influence on their breakdown strength. The first breakdown sites transferred to the boundary of Cu and Cr phase for CuCr25Ni compared to the Cr phase for CuCr25 without Ni.