The In Situ Generation Of High Energy Ball Milling The Al <sub> 2 </ Sub> O <sub> 3 </ Sub> / Cu Copper-based Electrical Contact Materials

This experiment prepares of Al₂O₃/Cu composite electric contactor materials by the high-energy ball mill combination with oxidation. High energy ball mill prepares Cu-Al solid alloy in this experiment, then suppress the powder by one-way repression, finally, sintering with oxidation generates Al₂O₃/Cu composite materials. This experiment acquired the best technical parameters of the high-energy ball mill through the studies of the ball mill medium, ball material than, ball mill, rotating speed and milling time and other parameters in ball mill process. Meanwhile, it researches the influence of the different contents of Al to Cu-Al solid effect; It adopts different thrust pressures for suppress in suppress experimental process and research material properties after suppress to determine the best repression pressure of compound materials; We adopt cover embedding method in sintering process which had a good sealing effect and greatly improved the sintering efficiency in the situation of ensuring oxygen partial pressure. Additionally ,the optimal sintering process parameters are obtained through the studies of oxidation medium ,oxygen partial pressure and sintering temperature and time .The results of the study indicate that:The diffraction peak of Al disappears completely after high-energy ball mill Cu and Al powder mixes for 21h, and the average granularity of powder reaches about 1μm ; By the preferred oxidation theory, the oxygen partial pressure is proportional to oxidation temperature. In this experiment, Cu₂O is as oxidant. Internal oxidation temperature should be chosen the ranges of 1107K-1320K and in this temperature region Cu₂O can be decomposed to release oxygen and oxygen is also easy to control; The best ratio of oxidation medium is Cu₂O: Al = 7:1 (mass ratio), the best compacting pressure is 900Mpa;The internal oxidation pr-ocess parameters are that: situ internal oxidation temperature is 950℃, the oxidation time is 4.5h. In the experimental conditions, we can prepare the Al₂O₃/Cu composite electrical contact materials and Al₂O₃ ceramic particles dispersed evenly distributed in the Cu matrix, Strengthening effect is obvious. The density of the materials can reach 87.6% and the conductivity reach 67.5IACS Hardness reached 148.0HVincreasing 2-3 times than pure copper.