(1. 北京有色金屬研究總院 有色金屬材料制備加工國家重點實驗室，北京 100088；
2. 寧波興業(yè)盛泰集團有限公司，寧波 315336)
摘 要: 采用金相顯微鏡、透射電子顯微鏡(TEM)等分析測試手段系統(tǒng)研究不同固溶、冷變形與時效組合工藝對低濃度Cu-Ni-Si合金的晶粒尺寸、析出相粒子尺寸及分布規(guī)律，同時對合金的力學與電學性能進行測試。結果表明，相對于其他四種工藝制度，低濃度Cu-Ni-Si合金經(jīng)過立式在線固溶處理+冷變形+時效組合形變熱處理工藝后，合金組織晶粒更加細小(平均晶粒尺寸為25 μm)，析出相分布更加彌散，抗拉強度為579 MPa，屈服強度為521 MPa，屈強比為0.9，伸長率為9%，導電率為52.2%IACS；與常用汽車連接器用C70250和TMg0.5合金綜合性能進行對比，低濃度Cu-Ni-Si合金具有優(yōu)良的綜合性能，在大功率電流使用時表現(xiàn)出良好的散熱性及可靠的尺寸穩(wěn)定性，可作為高強高導彈性材料廣泛應用于汽車連接器等領域。
關鍵字: 低濃度Cu-Ni-Si合金；時效處理；微觀組織；屈強比；應力松弛
（1. State Key Laboratory of Nonferrous Metals and Process, General Research Institute for Nonferrous Metals, Beijing 100088, China;
2. Ningbo Xingyeshengtai Group Co. Ltd., Ningbo 315336, China）
Abstract:The effects of different theromechanical treatments on grain size, precipitate size and distribution of precipitation phase of low concentration of Cu-Ni-Si alloy were investigated by metallurgical microscopy, transmission electron microscopy. The mechanical properties and electrical conductivity of the alloy were also tested. The results show that the Cu-Ni-Si alloy has excellent properties (tensile strength is 579 MPa, yield strength is 521 MPa, yield-tensile ratio is 0.9, elongation is 9% and electrical conductivity is 52.2%IACS ) and the average of grain size is 25 μm，when the alloy is solution treated at vertical bright annealing furnace, cold rolled and aging treatment, which is relative to other four heat treatment processes. Compared with C70250 and TMg0.5 alloys, the low concentration of Cu-Ni-Si alloy has a good heat dissipation and reliable dimensional stability in the use processes of high power current, which can be widely used in the automotive connector field.
Key words: low concentration Cu-Ni-Si alloy; ageing treatment; microstructure; yield-tensile ratio; stress relaxation
