RETRACTED ARTICLE: Enhanced tensile strength and thermal conductivity in copper diamond composites with B(4)C coating

Boron carbide (B(4)C) coating on diamond particle is synthesized by heating diamond particles in a powder mix of H(3)BO(3) and B in Ar atmosphere. The composition, bond state and coverage fraction of boron carbide coating on diamond particles are investigated. The boron carbide coating favors to grow on diamond (100) surface rather than on diamond (111) surface. Cu matrix composites reinforced with B(4)C-coated diamond particles were made by powder metallurgy. The addition of B(4)C coating gave rise to a dense composite. The influence of B(4)C coating on both tensile strength and thermal conductivity of the composite were investigated. When the B(4)C fully covered on diamond particles, the composite exhibited a greatly increase in tensile strength (115 MPa) which was much higher than that for uncoated-diamond/Cu (60 MPa) composites. Meanwhile, a high thermal conductivity of 687 W/mK was achieved in the B(4)C-coated-diamond/Cu composites.