Manufacturing Process And Property Of Al₂O₃ Strengthened Copper-based Composite Material

The Al₂O₃ particulates reinforced copper-based composites with high strength and high conductivity at ambient temperature have great potential applications in electrical industry and resistance welding industry. In the manufacturing process of the dispersion strengthened copper-based composite, the uneven distribution of the Al₂O₃ nanoparticles caused by the weak combination ability between Al₂O₃ and the copper will lead to the decrease of composite properties.This experiment was carried out in order to improve the bonding ability between Al₂O₃ and the copper by a synthetic method integrating Glycine- Nitrate Process (GNP) with mechanical alloying measure. Consequently, we can find a solution of the distribution problem of Al₂O₃ nanoparticles in the copper-base.Researches from several aspects, including metal ion proportion, Glycine proportion, effect of ethanol and time of ball rolling, on the Al₂O₃/Cu composite powder which was manufactured by a synthetic method integrating Glycine-Nitrate Process (GNP) and Mechanical alloying were carried out. The minimum Al₂O₃ content is 10wt. % when manufacture Al₂O₃/CuO powder with Glycine-Nitrate Process. If the Al₂O₃ content is lower than 10wt %, most of the productions will diffuse to the air from the container and become difficult to collect, ever lead to a blast since there will be a fierce airflow impact in the burning process. The optimal proportion of Glycine and metallic salt in this process is n [Glycine]: n [Al³⁺+Cu²⁺]=2:1. Lavation with ethanol is an effective solution to the problem of powder mass. It is found that the particle size will be finest after 60h's ball rolling and there will be few contributes to fine the particle size by increase the ball rolling time continuously.The technical parameter of Al₂O₃/Cu composites manufacturing are listed as following: sintering temperature is 850℃, sintering time is 1h. The repress of the green compacts is in the way of cold forging, forging proportion is 1:1. Annealing temperature is 800℃, lasting for 1h;The analysis results of the specimen's microstructure indicated that there was an improvement of the specimen's relative density by the treatment mentioned above;Al₂O₃ distributed fairly symmetrically in the specimen gained by Scheme B and no particle mass phenomenon was found there, while some Al₂O₃ particle massed in the specimen gained by Scheme C although most of them distributed symmetrically at the matrix.The properties examination results of Al₂O₃/Cu composites shows, the density and the conductivity of Al₂O₃/Cu composites decreased when the Al₂O₃ content increased. When the Al₂O₃ content is between 0.6 and 1.0wt %, the hardness and the transverse rupture strength of composite will increase with the increase of the Al₂O₃ content. On the contrary, the hardness and the transverse rupture strength of the specimen will decline when the Al₂O₃ content is over 1.0wt. %. Overall, the density, conductivity, hardness and transverse rupture strength of the specimen gained by Scheme B all presented higher compared with the specimen gained by Scheme C。...