Cu-Fe64Ni32Co4合金显微组织及热物理性能研究

Investigation on the Microstructures and Thermophysical Properties of Cu-Fe64Ni32Co4 Alloys

摘要:

本研究利用相图计算的CALPHAD方法和真空电弧熔炼技术,设计并制备了Cu_x(Fe_0.64Ni_0.32Co_0.04)_100-x(x=30, 45, 60, wt. %)系列合金。实验研究了该系列合金在不同热处理工艺时的显微组织,热导率以及热膨胀系数。研究结果表明：Cu-Fe₆₄Ni₃₂Co₄系列合金在600 °C和800 °C时效处理后均为fcc富铜相和fcc富因瓦(铁镍钴)相组成的各向同性的多晶合金。该系列合金在1000 °C淬火并在600 °C时效处理50 h后,其热膨胀系数变化范围为6.88~12.36×10_-6 K_-1；热导率变化范围为22.91~56.13 W.m_-1.K_-1；其热导率明显高于因瓦合金,其中Cu₃₀(Fe_0.64Ni_0.32Co_0.04)₇₀与 Cu₄₅(Fe_0.64Ni_0.32Co_0.04)₅₅合金的热膨胀系数可以与电子封装中半导体材料的热膨胀系数相匹配。

Abstract:

Based on the CALPHAD approach and vacuum arc melting technology, the Cu_x(Fe_0.64Ni_0.32Co_0.04)_100-x(x=30, 45, 60, wt. %) series alloys were designed and prepared. The effects of annealing process on microstructures, thermal conductivity (TC) and thermal expansion coefficients (CTE) were investigated in these prepared alloys. The result shows that the Cu-Fe₆₄Ni₃₂Co₄ isotropic polycrystalline alloys present two separate fcc phases (fcc Cu-rich phase and fcc (Fe, Ni, Co)-rich phase) microstructures after annealing at 600 °C and 800 °C. After annealing at 600 °C for 50 h, the CTE of the alloys ranged from 6.88 to 12.36×10_-6 K_-1. And TC varied from 22.91 to 56.13 W.m_-1.K_-1. Particularly, the TC are significantly higher than that of Invar alloy, and the CTE of Cu₃₀(Fe_0.64Ni_0.32Co_0.04)₇₀ and Cu₄₅(Fe_0.64Ni_0.32Co_0.04)₅₅ alloys can well match with that of semiconductor in electronic packaging.