内氧化-高速压制法制备Al2O3弥散强化铜合金的性能研究

摘要

Al2 O 3 dispersion copper alloy powder was made from Cu-0.18wt%Al alloy powder and oxidant Cu2 O powder through internal oxidation.Then the powder was pressed by high-velocity compaction (HVC)followed by sintering in hydrogen at 960-1 080 ℃ to prepare dispersion strengthened copper alloy.The forming ability of the alloy powder by HVC and the effects of sintering temperature on relative density (RD),hardness,electrical conductivity as well as compressive strength were investigated.The results show that HVC pressing Al2 O 3 dis-persion copper alloy powder could achieve good forming ability,and the green density reaches 8.72 g/cm3 (98.4%RD).Compared with the compact,RD of sintered alloy has no obvious change,while the electrical con-ductivity significantly improves,hardness decreases,and compressive strength increases.With increasing the sintering temperature, the electrical conductivity increases, hardness slightly decreases and compressive strength almost keeps constant.For the as-prepared alloy by sintering at 1 040-1 080 ℃,the electrical conduc-tivity and hardness was beyond 80% IACS and 77 HRB,respectively,and compressive strength reaches 453 MPa.These properties of the alloy could basically meet the requirement of the practical application used as spot welding electrodes.%以 Cu-0．18％(质量分数)Al 合金粉末为原料、Cu2 O 为氧化剂,采用内氧化法制备 Al2 O 3弥散铜合金粉末,采用高速压制(HVC)对粉末进行成形,经氢气中960~1080℃烧结制备弥散强化铜合金,研究合金粉末的 HVC 成形效果和烧结温度对合金致密度、硬度、导电率和压缩强度等性能的影响.结果表明,HVC 成形 Al2 O 3弥散铜合金粉能获得良好的成形效果,压坯密度达到8．71 g/cm3(98．4％致密度).与压坯相比,烧结后合金的致密度并无明显变化,但其导电率显著提升,硬度有所降低,压缩强度升高.随烧结温度的升高,合金的导电率有所升高,硬度略有降低,压缩强度基本保持恒定.经 1040~1080℃烧结制备合金的导电率、硬度分别达到80％ IACS 和77 HRB以上,压缩强度达到450 MPa,能基本满足点焊电极的实际应用需求.