Effects of Ag addition on electrical and thermal properties of Mo–Cu composites

• Appropriate Ag additive is beneficial to the sintering process.
• Mo–Cu composites with excellent electrical and thermal properties are prepared.
• The effect of Ag additive on the coefficient of thermal expansion is negligible.

In this work, Mo–Cu composites with improved electrical and thermal conductivities were fabricated by sintering Mo–Cu–Ag powders obtained from a microwave-assisted aqueous solution method, as Ag is added as activator with contents ranging from 0.5 wt.% to 2.0 wt.%. Effects of Ag additive on microstructure, electrical conductivity (EC), thermal conductivity (TC) and coefficient of thermal expansion (CTE) were investigated. Results show that Mo–Cu composites with evenly distributed microstructure can be obtained when the Ag content is 1.5 wt.%. Additionally, Mo–Cu composites with an addition of 1.5 wt.% Ag have the optimal desired properties, 27.82 × 106 Sm−1 for EC and 185.4 W m−1 K−1 for TC, respectively. However, if the Ag addition becomes beyond 1.5 wt.%, it will result in decrease in electrical and thermal conductivities and increase in coefficient of thermal expansion.