Cu-Sn-Bi合金在球磨和燒結過程中的組織演變Cu-Sn-Bi合金在球磨和燒結過程中的組織演變Microstructure evolution of Cu-Sn-Bi alloy in ball milling and sintering 采用機械合金化法制備出Cu-10%Sn-5%Bi合金粉末,然后將其壓制成型并進行燒結,制備成合金塊體;利用X射線衍射(XRD)和掃描電鏡(SEM)等分析手段,研究Cu-Sn-Bi合金在高能球磨和燒結過程中組織結構的變化。結果表明:高能球磨可以擴展Cu-Bi互不溶體系的固溶度,且在球磨過程中形成的Cu6Sn5相為亞穩(wěn)定相,隨著球磨時間延長會先形成而后發(fā)生分解,分解后的Sn將固溶到Cu中;同時在450 r/min球磨40 h后,Sn、Bi基本完全融入Cu中,形成Cu的過飽和固溶體。在燒結過程中,Bi從Cu中脫溶,細小彌散分布在Cu基體中。在700 ℃二次燒結后,Cu-Sn-Bi合金顯微組織良好,具有相對較好的力學性能。 The mechanical alloying (MA) was used to prepare Cu-10%Sn-5%Bi alloy powders. Then the bulk alloy was obtained by a combination of cold pressing and conventional powder sintering. The microstructure evolutions of Cu-10%Sn-5%Bi alloy during ball milling and sintering were investigated by XRD and SEM. The results show that high-energy milling can extend solid solubility of Cu-Bi immiscible system, and the metastable Cu6Sn5 phase successively happens to formation and decomposition with milling time. Meanwhile, the decomposition Sn is dissolved into Cu matrix. After milling with 450 r/min for 40 h, both Sn and Bi are completely dissolved into Cu matrix and a supersaturated solid solution of Cu(Sn, Bi) is formed. During sintering, Bi precipitates from Cu(Sn, Bi) supersaturated solid solution, are fine and dispersed homogeneously in Cu(Sn) matrix. The Cu-Sn-Bi alloy twice sintered at 700 ℃ exhibits an excellent microstructure and mechanical properties. 全文下載:https://pan.baidu.com/s/1qYDhHc4
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