(1. 北京科技大學 材料科學與工程學院,北京100083;
2. 中國兵器科學研究院 寧波分院,寧波 315103;
3. 內(nèi)蒙古科技大學 材料與冶金學院,包頭 014010)
摘 要: 采用噴射沉積技術制備Al-8.2Zn-2.2Mg-2.1Cu-0.14Zr-1.0Ni(質(zhì)量分數(shù),%)合金沉積坯,沉積坯經(jīng)熱擠壓變形后在不同溫度固溶處理,然后在(130 ℃, 24 h)條件下進行T6時效處理。通過對組織和性能分析,確定最佳固溶處理工藝。結果表明:加入1%Ni后沉積坯晶粒細小均勻,平均直徑為15 μm左右;在晶界和基體中有富Ni的Al3Ni2、Al7Cu4Ni 、MgNi2第二相粒子出現(xiàn),這些粒子在合金中主要起到彌散強化的作用;溶質(zhì)元素Zn、Mg、Cu的沉淀析出強化與球形富Ni粒子的彌散強化共同作用是使含1%Ni-7055鋁合金具有高強度高塑性的主要因素;經(jīng)擠壓變形(λ=3)和(475 ℃, 1.5 h)+(130 ℃, 24 h)熱處理后,合金管材縱向抗拉強度可達到690 MPa、伸長率為9.6%、布氏硬度為HB192。
關鍵字: Al-Zn-Mg-Cu合金;鎳元素;固溶處理;噴射沉積
(1. School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China;
2. Ningbo Branch of China Academy of Ordnance Science, Ningbo 315103, China;
3. School of Material and metallurgy, University of Science and Technology Inner Mongolia, Baotou 014010, China)
Abstract:High strength Al-8.2Zn-2.2Mg-2.1Cu -0.14Zr-1.0Ni(mass fraction, %) alloys, which was produced by spraying deposition method(the Osprey process), were heat treated at different solid-solutions, and all the aging treatments were at 130 ℃for 24 h. Microstructure characterization of the alloy was carried out by SEM, EDS and XRD, and the tensile properties of the alloy were tested. The result shows that many Ni-rich particles of Al3Ni2, Al7Cu4Ni and MgNi2, which provide a dispersive strengthening effect in the following solid-solution and ageing treatment, are dispersed both in grain-boundary and grain. The average grain size is approximately 15 μm. The remarkable strengthening while maintaining high levels of ductility is predominantly attributed to the precipitation hardening of solute elements and the dispersoid strength of spheroid Ni-rich particles. The highest ultimate tensile strength(UTS) for the pipe alloy(at an extrusion ratio of 3׃1) is 690 MPa at a ductility of 9.6% after the optimized solid solution and T6 aging.
Key words: Al-Zn-Mg-Cu alloy; Nickel element; solid-solution treatment; spraying deposition


