(1. 華南理工大學(xué) 材料科學(xué)與工程學(xué)院，廣州 510640； 2. 華南理工大學(xué) 機(jī)械與汽車工程學(xué)院，廣州 510640； 3. 廣東省先進(jìn)儲(chǔ)能材料重點(diǎn)實(shí)驗(yàn)室，廣州 510640； 4. 廣東水利電力職業(yè)技術(shù)學(xué)院，廣州 510925)
摘 要: 采用機(jī)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(jìn)行燒結(jié)，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(jié)過程中組織結(jié)構(gòu)的變化。結(jié)果表明：高能球磨可以擴(kuò)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(shí)間延長(zhǎng)會(huì)先形成而后發(fā)生分解，分解后的Sn將固溶到Cu中；同時(shí)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(jié)過程中，Bi從Cu中脫溶，細(xì)小彌散分布在Cu基體中。在700 ℃二次燒結(jié)后，Cu-Sn-Bi合金顯微組織良好，具有相對(duì)較好的力學(xué)性能。
關(guān)鍵字: 機(jī)械合金化；粉末燒結(jié)；Cu-Sn-Bi合金；過飽和固溶體
（1. School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; 2. School of Mechanical & Automotive Engineering, South China University of Technology, Guangzhou 510640, China; 3. Key Laboratory of Advanced Energy Storage Materials of Guangdong Province, Guangzhou 510640, China; 4. Guangdong Polytechnic of Water Resources and Electric Engineering, Guangzhou 510925, China）
Abstract: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.
Key words: mechanical alloying; powder sintering; Cu-Sn-Bi alloy; supersaturated solid solution
