2015 Volume 56 Issue 652 Pages 407-412
Thermal properties of Cr-Cu for heat-sink application are required to be close to those of Mo-Cu and W-Cu. The rolled and Cu-clad and rolled Cr-Cu infiltrated compacts are investigated to improve the thermal properties. In the rolled Cr-Cu material, Cr phases are significantly elongated and flattened, resembling a fibrous structure. Such a fibrous structure of Cr phases makes the thermal expansion coefficient much lower than that predicted from the rule of mixture. While the flattened Cr structure promotes thermal flow in the in-plane direction, it deteriorates that in the thickness direction. To improve thermal conductivity in thickness direction, the Cr-Cu compact was bonded with a Cu plate and rolled. The clad and rolled structure enables the improvement of thermal conductivity in the thickness direction without degrading the thermal expansion coefficient in the rolling direction.