Microstructure and Properties of a Cu-Ni-Sn Alloy Treated by Two-Stage Thermomechanical Processing
Microstructure and Properties of a Cu-Ni-Sn Alloy Treated by Two-Stage Thermomechanical Processing
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两阶段形变处理Cu-Ni-Sn合金的组织与性能
DOI：
10.1007/s11837-019-03606-5
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发表时间：
2019-08-01
期刊：
影响因子：
2.6
通讯作者：
Fang, Mei
中科院分区：
文献类型：
--
作者：
Jiang, Yexin;Li, Zhou;Fang, Mei
采用金相显微镜、扫描电子显微镜、透射电子显微镜和力学性能测试等手段，研究了两步形变形变工艺对Cu15Ni8Sn1.0Zn 0.5Al 0.2Si合金组织和性能的影响。预时效合金中出现了调幅分解和具有L12有序结构的β-Ni3Sn相。铜基体与β-Ni3Sn析出物之间的晶体取向关系为(2 0 0)Cu||(10 0)β，[0 0 1]Cu||[0 0 1]β和()Cu||()β，[1 12]Cu||[1 2]β。合金的高强度主要归因于析出强化和亚结构强化的综合作用。在预时效过程中形成的初生纳米粒子与在冷轧过程中形成的位错组态之间的相互作用促进了基体中的析出，抑制了晶界上胞状和粗大析出相的形成，从而改善了合金的综合性能。经两级形变处理后的峰值时效合金的硬度为387×HV，电导率为8.5%IACS，抗拉强度为1176×10-6×10-6 Mpa，屈服强度为1106×10-6×10-6 Mpa，延伸率为3.86%，强塑性积为4539×10-5 Mpa%。
The effects of two-stage thermomechanical processing on the microstructure and properties of Cu-15Ni-8Sn-1.0Zn-0.5Al-0.2Si alloy have been investigated by optical microscopy, scanning electron microscopy, transmission electron microscopy, and mechanical and electrical property testing. Spinodal decomposition and β-Ni3Sn precipitates with L12ordering structure appeared in the preaged alloy. The crystal orientation relationships between the copper matrix and β-Ni3Sn precipitates were (200)Cu||(100)β, [001]Cu||[001]βand ()Cu||()β, [112]Cu||[112]β. The high strength of the studied alloy can mainly be attributed to the combined effects of precipitation strengthening and substructure strengthening. The interaction between the nascent nanoparticles that form during pre-aging and the dislocation configurations that form during cold rolling promotes precipitation in the matrix and suppresses formation of cellular precipitates and coarse precipitates at grain boundaries, improving the comprehensive properties of the alloy. The peak-aged alloy treated with two-stage thermomechanical processing showed hardness of 387 HV, electrical conductivity of 8.5%IACS, tensile strength of 1176 MPa, yield strength of 1106 MPa, elongation of 3.86%, and strength–ductility product of 4539 MPa%.