(西安理工大學(xué) 陜西省電工材料與熔(浸)滲技術(shù)重點(diǎn)實(shí)驗(yàn)室，西安 710048)
摘 要: 采用真空感應(yīng)熔煉制備Cu-Cr-Zr-Mg合金，研究Mg含量及冷卻方式對(duì)Cu-Cr-Zr-Mg合金組織與性能的影響。結(jié)果表明：Cu-Cr-Zr-Mg合金鑄態(tài)組織為α-Cu相和Cu-Cr共晶相所構(gòu)成。隨著Mg的添加，合金中二次枝晶臂間距明顯減小，組織細(xì)化。經(jīng)固溶時(shí)效處理后，納米級(jí)CrCu2(ZrMg)相從銅基體中析出，合金的硬度與導(dǎo)電率大幅度提升。當(dāng)Mg含量為0.3%(質(zhì)量分?jǐn)?shù))時(shí)，合金的綜合性能最佳，硬度為138.3HB，導(dǎo)電率為79.1%IACS。與感應(yīng)熔煉合金組織相比，采用銅模冷卻的合金組織更加細(xì)小均勻，偏析少，經(jīng)固溶時(shí)效處理后析出相尺寸明顯減小，且析出相數(shù)量增多，合金的硬度和導(dǎo)電率分別達(dá)到156.8HB和82.8%IACS，合金抗拉強(qiáng)度達(dá)到451.8 MPa。
關(guān)鍵字: Cu-Cr-Zr-Mg合金；快速冷卻；細(xì)晶強(qiáng)化；析出相
（Shaanxi Province Key Laboratory of Electrical Materials and Infiltration Technology, Xi’an University of Technology, Xi’an 710048, China）
Abstract:Cu-Cr-Zr-Mg alloys were prepared by vacuum induction melting method. The effects of Mg contents and cooling method on the microstructure and properties of Cu-Cr-Zr-Mg alloy were studied. The results show that the microstructure of as-cast Cu-Cr-Zr-Mg alloy is α-Cu phase and Cu-Cr eutectic structure. With the addition of Mg, the secondary dendrite arm spacing of the alloy decreases significantly and the microstructure is refined. After solution treatment and aging treatment, the nano-sized CrCu2 (ZrMg) phase precipitates from the matrix, and the hardness and electrical conductivity of the alloy are greatly improved. When the Mg content is 0.3% (mass fraction), the alloy obtains the best overall performance, with the hardness of 138.3HB and the electrical conductivity of 79.1%IACS. Compared with the furnace cooling alloy, the structure of the alloy cooling in the copper mold is finer and more uniform, and the segregation is less. After the solution treatment, the precipitated phase size obviously decreases, and the number of precipitated phases increases. The hardness and electrical conductivity reach 156.8HB and 82.8%IACS, respectively, and the tensile strength reaches 451.8 MPa.
Key words: Cu-Cr-Zr-Mg alloy; rapid cooling; fine grain strengthening; precipitation phase
