Influences of melt treatment on grain sizes and morphologies of AZ91D alloy

• Published in: Transactions of Nonferrous Metals Society of China Vol. 17; no. 5; pp. 887 - 892
• Main Author: 齐祥超 唐靖林 李双寿 曾大本
• Format: Journal Article
• Language: English
• Published: Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China%Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China 01.10.2007; Key Laboratory for Advanced Materials Processing Technology, Ministry of Education, Tsinghua University,Beijing 100084, China
• Subjects: AZ91D合金; 溶解加工; 电磁搅拌; 颗粒形态学; electromagnetic stirring; grain morphology; melt treatment; grain size; AZ91D alloy
• ISSN: 1003-6326
• DOI: 10.1016/S1003-6326(07)60194-0

Influences of the three melt treatment processes （namely, refinement with carbon inoculation, electromagnetic stirring and ＂refinement ＆ electromagnetic stirring＂ processing） on the microstructures of AZ91D alloy were explored experimentally. The results indicate that the micron carbon powders inoculation processing with 0.1% （mass fraction） addition level makes the grain size of the primary phase （a-Mg） decrease to approximate 40% that of the initial primary crystal, from about 530 μm to 200 μm around. The electromagnetic stirring processing not only decreases the grain sizes sharply, but also transfers the grain shape of a-Mg from coarse dendritic to nearly spheralitic with the shape factor from about 0.1 to approximate 0,8. And the ＂refinement ＆ electromagnetic stirring＂ processing improves grain shape of a-Mg further and refines grain size to about 72 μm, less than 15% that of the initial primary crystal.