Cu-Ni-Si合金加工工艺与性能的研究

Processing Technology and Property of Cu-Ni-Si Alloy

Cu-Ni-Si合金是典型的时效硬化铜合金,常用作引线框架材料。熔炼、铸造了一种成分为Cu-2.28Ni-0.67 Si的铜合金铸锭,尺寸为20 mm×80 mm×250 mm,并热轧成7.5 mm厚的板坯;分别在800℃、850℃和900℃进行固溶处理,然后以60%的压缩率冷轧至3 mm厚的薄板,再分别于400℃、450℃和500℃时效1 h、2 h、4 h、6 h、8 h和10 h。研究了合金在不同状态的显微组织、力学性能和电导率。结果表明,经850℃固溶处理、500℃时效8 h的合金综合性能最好:抗拉强度为510 MPa,断后伸长率为19.8%,硬度为165 HV,电导率为30.4%IACS。

Cu-Ni-Si alloy is a typical copper alloy able to be age hardened, and commonly used as lead-frame material. An ingot having composition of Cu-2.28Ni-0.67Si, 20 mm thick by 80 mm wide by 250 mm long, was produced by smelting and pouring, and was hot rolled into 7.5 mm thick billet. Subsequently, the billet was solution treated at 800℃, 850 ℃ and 900 ℃, respectively, and cold rolled at reduction of 60% into 3 mm thick sheet, and then aged at 400 ℃, 450℃ and 500 ℃ for 1 h, 2 h, 4 h, 6 h, 8 h, and 10 h, respectively. The microstructure, mechanical properties and electrical conductivity of the alloy in different conditions were examined. The results show that the alloy solution treated at 850 ℃and aged at 500℃ for 8 h exhibits the best combination of properties such as tensile strength of 510 MPa , elongation of 19.8%, hardness of 165 HV, and electrical conductivity of 30.4% IACS.