Effect of Bi addition on microstructures and mechanical properties of AZ80 magnesium alloy  

添加Bi对AZ80镁合金显微组织及力学性能的影响(英文)

作　　者：王亚霄[1] 周吉学[2] 王杰[1] 罗天骄[1] 杨院生[1] 

机构地区：[1]中国科学院金属研究所,沈阳110016 [2]山东省科学院新材料研究所,济南250014

出　　处：《Transactions of Nonferrous Metals Society of China》2011年第4期711-716,共6页中国有色金属学报（英文版）

基　　金：Project(2007CB613700)supported by the National Basic Research Program of China

摘　　要：The effects of Bi addition on the microstructures and mechanical properties of as-cast AZ80 alloy were investigated. The results show that with the addition of Bi, the coarse eutectic phases are refined and become discontinuous; some flaky and granular Mg 3 Bi 2 phases with a hexagonal structure of D5 2 are observed along the grain boundaries and between dendrites. The tensile strength and elongation increase first, and then decrease with increasing Bi content. AZ80-0.5%Bi alloy has optimum combination mechanical properties. When the content of Bi is above 1.0% （mass fraction）, the amount of flaky Mg 3 Bi 2 phase increases markedly, which splits the matrix and deteriorates the tensile strength and elongation.研究添加Bi对AZ80镁合金铸态显微组织及力学性能的影响。结果表明:将Bi加入到AZ80镁合金中后,粗大的β-Mg17Al12离异共晶组织被细化并由连续网状分布变为断续状;晶界处和枝晶间出现具有六方D52结构的针状和颗粒状的Mg3Bi2相。力学性能测试结果表明:随着Bi含量的增加,抗拉强度和伸长率先升高再降低,AZ80-0.5%Bi合金的综合力学性能最优;当Bi含量超过1.0%(质量分数)时,针状相明显变多并粗化,加载时容易开裂而割裂基体,导致力学性能降低。

关 键 词：AZ80 magnesium alloy BISMUTH MICROSTRUCTURE mechanical property 

分 类 号：TG146.22[一般工业技术—材料科学与工程]