Effect of oxygen on the mechanical properties of copper and copper-matrix composites hardened by melt-synthesized chromium carbides

Resumo

Thermal analysis is used to study the saturation of the copper melt by oxygen from an oxygen-containing gas phase and the possibility of deoxidation of this melt by nanosized diamond–graphite, which enters in the reaction mixture used to synthesize chromium carbide in the production of copper-matrix composites, are studied. The oxygen and chromium carbide contents are found to affect the mechanical properties of copper and copper-matrix composites. Diamond–graphite is shown to have a high refining ability, which can substantially increase the plasticity of copper and copper-matrix composites. A low chromium carbide content is found to play a modifying role in grain refinement, and a high chromium carbide content is shown to cause the formation of a precipitation-hardened structure and an increase in the physicomechanical properties of copper-matrix composites.