Heterogeneous interfacial chemical nature and bonds in a W-coated diamond/Al composite

• Heterogeneous multi-interfaces are developed in a W-coated diamond/Al composite.
• Formation of interfacial Al4C3 crystals is associated with local O enrichment.
• Presence of Al12W interfacial particles promotes interfacial chemical bonding.

Heterogeneous Al/Al4C3/Al2O3/diamond{111}, Al/nanolayered Al4C3/diamond{111} and Al12W particle/Al4C3/Al2O3/diamond{111} multi-interfaces have been developed at the nanoscale in a W-coated diamond/Al composite produced by vacuum hot pressing. The formation of nanoscale Al4C3 crystals is strongly associated with local O enrichment and can be further promoted by Al12W interfacial particles. The latter effectively contributes to enhance interfacial chemical bonding reducing interfacial thermal resistance and, in turn, enhancing thermal conductivity.