石墨表面化学镀Cu对天然鳞片石墨/Al复合材料热物理性能的影响

Thermal conductivity and mechanical properties of flak graphite/Al composite with electroless Cu plating on graphite surface

摘要: 对天然鳞片石墨（GF）进行化学镀Cu的表面处理，对化学镀Cu石墨（Cu-GF）和Al粉采用真空热压的工艺制备出镀Cu石墨/Al（Cu-GF/Al）复合材料。研究了Cu-GF/Al复合材料的微观结构和微观界面，同时也研究了Cu-GF对Cu-GF/Al复合材料热导率和抗弯性能的影响。结果表明，GF上的Cu层能抑制界面脆弱相Al₄C₃的产生，使Cu-GF/Al复合材料的抗弯性能有了显著提升。当Cu-GF体积分数从50%增加到70%时，Cu-GF/Al复合材料的抗弯强度也从104 MPa降低到74 MPa。当GF体积分数为70%时，Cu-GF/Al复合材料的热导率达到最高值为522 W/（m·K）。

Abstract: Cu was coated on the surface of the nature graphite flake (GF) by the electroless copper plating method, and then the Cu-GF/Al composites were fabricated by vacuum hot-press sintering with Cu-coated GF (Cu-GF) and Al powder. The microstructures and interfaces of Cu-GF/Al composites were studied and the effect of Cu-GF surface on the thermal conductivity and bending strength was investigated. The results show that the Cu layer inhibits the formation of Al₄C₃. Thus the bending strength of Cu-GF/Al composites is significantly enhanced after Cu coated and the value decreases from 104 to 74 MPa as Cu-GF volume fraction increases from 50% to 70%. The maximum thermal conductivity is 522 W/(m·K) when the volume fraction of GF is 70%.