应用新型生产线固溶处理工艺对Cu-2.8N i-0.7S i-0.1Mg合金进行处理,研究了时效温度、时效时间和时效前不同变形量对Cu-2.8N i-0.7S i-0.1Mg合金微观组织和性能的影响。结果表明,合金在450℃时效时,第二相呈细小弥散状态分布在基体上,能获得较好的综合性能,在450℃时效4 h时,其导电率和显微硬度分别可达38.13%IACS和212.6 HV。经过对选区电子衍射花样的标定,析出相为N i2S i。合金经冷轧变形后内部出现大量的晶体缺陷,能在时效初期促进第二相的析出,使合金具有更好的综合性能,合金经60%变形后在450℃时效1 h后其导电率和显微硬度分别可达38.78%IACS和232.1 HV。继续升高时效温度或延长时效时间会引起第二相长大而导致显微硬度的升降。通过对生产线固溶和常规实验室固溶处理的合金进行性能比较,生产线固溶态合金的显微硬度时效后低于常规固溶处理合金,这可能是由生产线固溶时的不彻底性所导致。
Cu-2.8Ni-0.7Si-0.1Mg alloy was treated by new solid solution technology on production line in this investigation and the effects of aging temperature,aging time,and different cold deformation on microstructure and properties were studied.The results showed that the secondary phase,which was identified as Ni2Si based on the selected-area electron diffraction(SAED) pattern,was dispersedly distributed in the matrix after aging at 450 ℃ and then favorable comprehensive properties were achieved.After aging at 450 ℃ for 4 h,high values of properties were obtained with electrical conductivity of 38.13%IACS and microhardness of 212.6 HV.Cold deformation could lead to the high density of the lattice defects,accelerating the process of precipitation,which further enhanced the comprehensive properties.After 60% cold deformation followed by aging at 450 ℃ for 1 h,high values of properties were obtained with electrical conductivity of 38.78%IACS and microhardness of 232.1 HV.Further increase of aging temperature and time could lead to the growth of the secondary phase and thus decrease of microhardness.Comparing with the properties for alloys treated between on production line and by common solid solution in the lab,the value of microhardness after aging for solid solution on production line was lower than that after solid solution the lab,which might be attributed to incomplete solution treatment.