【作者】 唐琳；

【导师】 罗丰华；

【作者基本信息】 中南大学 ， 工程硕士（专业学位）， 2014， 硕士

【摘要】 随着工业的发展,高强高导铜合金在电子、电力行业的应用优势日益凸显,Cu-Ag合金作为高强度、高导电铜合金中的佼佼者,高温性能却不太理想。通过在合金中添加一定含量的Zr,能有效提高Cu-Ag合金的强度及高温稳定性。本文以真空熔炼的方法制造Cu-3Ag-Zr合金,通过添加不同含量的Zr,以及对合金进行不同的热处理工艺处理,探讨了Zr含量对Cu-3Ag-Zr合金性能与组织的影响,不同热处理工艺下合金的性能与组织,以及合金的强化机制。研究表明：随着Zr含量的增加,合金硬度与强度会随之升高,合金的晶粒组织细化,再结晶过程被抑制,再结晶温度提高,热稳定性增强。提高固溶温度或延长固溶时间都能提高Cu-Ag-Zr合金的屈服强度。固溶之后时效之前的冷变形处理能加快Cu-3Ag-Zr合金时效初期的析出进程,使合金力学性能的峰值出现时间提前。时效前的冷变形能够显著提高合金的力学性能,Cu-3Ag-0.6Zn合金固溶后进行80%冷变形后在450℃时效处理2h可获得542MPa的屈服强度,595MPa的抗拉强度以及10.4%的延伸率。固溶态Cu-Ag-Zr合金的强化主要是通过Ag、Zr作为溶质原子溶入基体中,使晶格产生畸变,从而获得固溶强化的效果,同时也有Ag粒子作为沉淀相阻碍位错的运动,使得合金强度升高。时效态Cu-Ag-Zr合金的强化机制包括Ag、Zr作为溶质原子对合金起到的固溶强化,时效过程中析出的大量的Ag粒子以及Cu5Zr粒子对合金造成的沉淀强化作用。更多还原

【Abstract】 With the development of industry, the advantages of high-strength and high-conductivity copper alloys in electronic application has become increasingly prominent. Cu-Ag alloy have high strength and high conductivity, but its elevated temperature properties is not that ideal. By adding a certain content of Zr, the strength and high-temperature stability of Cu-Ag alloy can be effectively improved.The Cu-3Ag-Zr alloy was prepared by vacuum induction melting. By adding different amounts of Zr, as well as different heat treatment process, the effect of content of Zr on properties and microstructure of Cu-3Ag-Zr alloy was investigated. And also, the mechanical properties, micro structures and strengthen mechanism of Cu-3Ag-Zr alloy under different heat treatment states were studied.The results show that:with the increases of Zr contents, the grain refinement and recrystallization is inhibited, the mechanical performance, recrystallization temperature and thermal stability of alloy is enhanced.Either improve solid solution temperature or extent solid solution time, the yield strength of Cu-Ag-Zr alloy would increase. The cold deformation prior to aging can accelerate the precipitation process of Cu-Ag-Zr alloy in early aging, which contribute to the appearance of the peak of mechanical properties. Cold deformation before aging can significantly improve the mechanical properties of Cu-Ag-Zr alloy, the yield strength, tensile strength and elongation of Cu-3Ag-0.6Zr alloy can reach 542MPa, 595MPa and 10.4% respectively after prepared by solid solution treatment, 80% cold deformation and aging at 450℃ for 2h.After solid solution treatment, Ag and Zr dissolves in the matrix of Cu-Ag-Zr alloy and lead to the lattice distortion, resulting in solid solution strengthening effect. At the same time, the presence of precipitates Ag hinder dislocation movement, thereby the strength ofthe alloy is improved.The strengthen mechanism of aged Cu-Ag-Zr alloy including solid solution strengthening which is caused by solute atom Ag and Zr, and precipitation strengthening which is caused by Ag particles and CusZr particles that precipitated during aging.更多还原