Design of tailored oxide-carbide coating on carbon fibers for a robust copper/carbon interphase

摘要

The lack of robust interphases between carbon and most metals prevent the exploration of the full scope potential of carbon-based metal matrix composites. Here, we demonstrated a scalable and straightforward way to produce strong interphase between copper (Cu) and carbon fibers (CFs) by designing a tailored titanium oxide-carbide coating (TiOy-TiCx) on CFs in a molten salt process. The oxide-carbide composition in the graded layer strongly depends on the coating temperature (800-950 degrees C). A coating with a high TiOy content obtained at a low coating temperature (800 degrees C) contributes to better molten-Cu wetting and strong adhesion energy between CFs and Cu during a subsequent exposure at 1200 degrees C. The Cu wetting angle for the TiOy-TiCx-CF sample obtained at 800 degrees C was similar to 80 degrees +/- 5 degrees with a Cu surface coverage of similar to 50% versus similar to 115 degrees and similar to 10% for the TiCx-CF sample made at 950 degrees C. The kinetic analysis of the coating process step by step suggests a growth rate limited by the mass-transfer through the coated layer. This method provides a novel approach to improve the thermal conductivity of Cu/C composite for thermal management applications. (C) 2019 Elsevier Ltd. All rights reserved.