Sr对Mg-5Al-0.8Ca-0.2La镁合金显微组织及高温性能的影响  

Effects of Sr on the Microstructure and Mechanical Properties at Elevated Temperature of Mg-5Al-0.8Ca-0.2La Magnesium Alloy

作　　者：李晓斌[1] 王社斌[1,2] 王帅[1] 范晋平[1] 许并社[1,2] 

机构地区：[1]太原理工大学材料科学与工程学院,山西太原030024 [2]太原理工大学教育部新材料界面与工程重点实验室,山西太原030024

出　　处：《太原理工大学学报》2009年第2期173-176,共4页Journal of Taiyuan University of Technology

基　　金：国家自然科学基金重大研究计划资助项目(90306014);国家自然科学基金资助项目(20271037;20471041)

摘　　要：研究了Sr对Mg-5Al-0.8Ca-0.2La镁合金显微组织与室温和高温力学性能的影响。实验结果表明,Sr的加入显著细化了基体合金的显微组织,抑制了-βMg17Al12相的析出;并且在晶界上析出了Mg-Al-Sr,Al2Ca和Al11La3耐热相,提高了晶界的高温稳定性。Sr的加入虽然导致合金的室温抗拉强度和延伸率下降,但提高了合金高温抗拉强度,也略提高了室温和高温屈服强度。The effects of Sr on microstructure, mechanical properties at ambient and elevated temperatures of Mg-5Al-0.8Ca-0.2La magnesium alloy were studied. The results show that the a-Mg matrix is refined with the addition of Sr, the β-Mg17Al12 phase is restrained,and few heat-resistant phases are precipitated at the grain boundary（Mg-Al-Sr, Al2Ca and Al11 La3 ）, which improves the stability of the grain boundary at elevated temperature. Though the addition of Sr into the alloy decreases the tensile strength and elongation at ambient temperature, the tensile strength at elevated temperature is improved remarkably. The yield strength at both ambient and elevated temperature also increase a bit.

关 键 词：耐热镁合金 锶 显微组织 高温力学性能 

分 类 号：TG146.27[一般工业技术—材料科学与工程] TG146.453[金属学及工艺—金属材料]