Diamond Etching Enhances the Thermal Shock Resistance of Diamond/Copper Composites

Diamond Etching Enhances the Thermal Shock Resistance of Diamond/Copper Composites

Diamond/copper (Dia/Cu) composites are highly promising materials due to their exceptional thermal conductivity (TC) and adjustable coefficient of thermal expansion (CTE). However, conventional Dia/Cu composites are susceptible to thermal shock due to CTE mismatches, which induce fatigue and degradation.

In advanced manufacturing and powder metallurgy, diamond surface metallization is commonly employed to enhance thermal conductivity and wear resistance. Tungsten is often selected as a coating material due to its high intrinsic TC and low solubility in copper. While traditional diamond surface treatments improve thermal conductivity, they fail to address the critical issue of poor thermal shock resistance. This limitation arises from the significant CTE disparity between the reinforcement and the matrix, leading to thermal stress at the interface. When stress exceeds a critical threshold, interfacial damage occurs, increasing thermal resistance and reducing overall conductivity. Enhancing the thermal shock resistance of Dia/Cu composites is essential for broader applications and remains a key research focus.

By employing an etching process, the interface morphology of Dia/Cu composites was transformed from a smooth to a rough, tortuous structure. This modification effectively suppressed crack propagation, significantly improving the material’s thermal shock resistance.