熔炼工艺对Cu-Ni-Nb合金组织及导热性能的影响

Effects of Melting Process on Microstructure and Thermal Conductivity of Cu-Ni-Nb Alloy

采用真空电弧熔炼工艺制备了Cu-Ni-Nb合金,研究了Nb的加入方式和加入量对Cu-Ni-Nb合金组织、热导率和熔点的影响。结果表明,采用一次熔炼法,难以将高熔点Nb熔入Cu-Ni合金。采用二次熔炼法,以Nb-Ni中间合金方式可使Nb熔入Cu-Ni合金,生成Ni3Nb、Ni8Nb等第二相。Cu-Ni-Nb合金热导率随Nb含量的增加而提高,合金熔点随着Nb含量的增加而下降。Cu-20Ni-3Nb合金热导率为43.23 W/(m·K),熔点为1 146℃。

Effects of adding method and addition content of niobium element on the microstructure, ther- mal conductivity and melting point of the Cu-Ni-Nb alloy were investigated by vacuum arc melting process. The results show that it is difficult to mix the high melting point element Nb into Cu-Ni alloy only by one smelting. However, the Nb element can be dissolved into the Cu-Ni alloy in style of Nb-Ni master alloy by using two steps melting. Some new phases such as Ni3Nb, NisNb are generated. In ad- dition, with the increase of Nb content, the thermal conductivity the Cu-Ni-Nb alloy prepared is in- creased while the melting point of the alloy is decreased. The thermal conductivity of Cu-20Ni-3Nb alloy reaches 43.23 W/（m . K）, and the melting point is 1 146 ℃.