Microstructure And Properties Of Al₂O₃/Cu Composites Prepared By Reaction-Casting

A series of Al2O3/CU composites were synthesized by Reaction -Casting in which the mixed-powders of Cu2O and Al as a modification agent was added to liquid copper and then cooled in a die mould. The effects of the reaction temperature, the quantity of mixed-powders, the cold working and the anneal temperature on microstructure and properties of the composites were studied. The results showed that:1. From the thermodynamics and kinetics point of view, Al2O3 particles can be got by the reaction between Cu2O and Al in molten copper.2. With the increase of the reaction temperature, the reaction between Cu2O and Al became more complete. When the temperature of molten copper reached 1240℃, the prepared Al2O3/CU composites had better properties.3. The better properties of Al2O3/CU composites were got by adding 3.5% mixed-powders in the molten copper.4. The properties of the prepared Al2O3/CU composites, when adding the mixed-powders with a ratio of 4(Cu2O) to 1(Al), are better than that when adding mixed-powders with a ratio of 6(Cu2O) to 1 (Al).5. The prepared Al2O3/CU composites have a good cold deformation ability. After 50% cold deformation, the brinell hardness of the Al2O3/CU composites significantly increased, reached 116, but the electric conductivitychanged a little.6. The softening temperature of the Al2O3/Cu composites reached 400 ℃ which is higher than that of Cu.