均匀化退火处理对AZ91镁合金热轧变形组织与力学性能的影响  

Effect of Homogenizing Annealing Treatment on Hot-Rolled Microstructure and Mechanical Properties of AZ91 Magnesium Alloy

作　　者：郑留伟[1,2,3] 梁伟[1,2] 赵子龙[1,2] 李亚娥[1,2] 王红霞[1,2] 王一德[1,4] 

机构地区：[1]太原理工大学,山西太原030024 [2]先进镁基材料山西省重点实验室,山西太原030024 [3]山西工程职业技术学院,山西太原030009 [4]太原钢铁集团有限公司,山西太原030003

出　　处：《稀有金属材料与工程》2016年第5期1296-1301,共6页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51474152)

摘　　要：为改善铸态AZ91镁合金组织不均匀性,提高其轧制成型能力,研究了均匀化退火处理对AZ91镁合金轧制变形前后微观组织及力学性能的影响。结果表明:均匀化退火处理可以有效改善合金组织中第二相分布;经400℃、多道次轧制后,沿晶界分布的细长条状Mg_(17)Al_(12)相数量显著减少,部分脆性Mg_(17)Al_(12)相发生断裂,以小颗粒状弥散分布于晶界附近和基体内部。均匀化后轧制合金比铸态轧制合金强度略有提高,而伸长率提高达50%。轧制后合金的拉伸断口形貌也显示合金塑性得到明显改善。To improve the inhomogeneity and rolling forming ability of as-cast AZ91 magnesium alloy, the effect of homogenizing annealing treatment on microstructure and mechanical properties of AZ91 magnesium alloy before and after rolling deformation was studied. The results show that the distribution of second phase in the alloy tissue is improved effectively after homogenization annealing treatment. After multi-pass rolling at 400 ℃, the thin strip Mg17Al12 phase which originally distributes along the grain boundaries reduces significantly with some of them fragmenting, and some distribute near the grain boundaries or inside the grains as small particles. Compared with the strength of as-cast rolled alloy, the strength of rolled alloy after homogenization increases slightly; while the elongation increases by 50%. The tensile fracture morphology after rolling indicates that the ductility of alloy improves markedly.

关 键 词：均匀化退火处理 AZ91镁合金 轧制 Mg17Al12相 

分 类 号：TG146.22[一般工业技术—材料科学与工程]