AZ31B镁合金电磁超声铸轧板后续温轧的组织和织构演变  

Evolution of microstructure and texture of electromagnetic and ultrasonic energy-field cast-rolling AZ31B Mg alloy sheet during subsequent warm-rolling process

作　　者：李建平[1] 肖琼[1] 毛大恒[1] 扶宗礼[1] 石琛[1] 

机构地区：[1]中南大学高性能复杂制造国家重点实验室,湖南长沙410083

出　　处：《中南大学学报（自然科学版）》2013年第12期4811-4818,共8页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(50974139)

摘　　要：分别对AZ31B镁合金普通／复合能场（电磁场＋超声波）铸轧板在250℃下进行7个道次轧制，道次压下量为15％，对比分析了整个轧制过程中两种铸轧镁板组织及织构的演变规律。研究表明：复合能场铸轧板比普通铸轧板提前1个道次完成动态再结晶，再结晶晶粒的平均尺寸（4～6gm）比普通铸轧板的平均尺寸（8～10μm）小。复合能场铸轧板与普通铸轧板相比，原始织构的强度较低，各织构组分分布较均匀，锥面织构组分分布较高，择优取向较弱；复合能场铸轧板在前3个道次轧制过程中其主要织构（基面织构）强度增加较快，后四个道次则增加变缓，而普通铸轧板前3个道次增加较慢，后4个道次增加明显。每个道次复合能场铸轧板的屈服强度、抗拉强度和伸长率均高于相应道次的普通铸轧板。AZ31B Mg alloy sheets were rolled by seven passes with pass reduction of 15% at 250℃. The specimens were deformed by normal cast-rolling and combining energy-field cast-rolling （electromagnetic field and ultrasonic）. Both microstructure and texture of two kinds of Mg sheets during whole rolling process were analyzed. The results show that in comparison to normal cast-rolling Mg sheet with the average grain diameter of 8-10 μm, the process of dynamic recrystallization of the combining energy-field Mg sheet with the average grain diameter of 4-6 pm is advanced by one pass. In contrast to normal cast-rolling Mg sheet, the texture intensity of combining energy-field Mg sheet is lower and the distribution of every kind of texture components is more homogeneous, and the proportion of conical plane texture is higher and preferred orientation is weaker. The intensity of main texture, basal plane texture, of combining energy-field Mg sheet increases rapidly in the previous three rolling processes and increases slowly in the following four processes, while that of normal Mg sheet increases slowly in the previous three rolling processes and increases rapidly in the following four processes. The yield strength, ultimate tensile strength and elongation of combining energy-field Mg sheet are all higher than those of the normal Mg sheet.

关 键 词：AZ31B镁合金 复合能场 动态再结晶 织构 

分 类 号：TG166[金属学及工艺—热处理]