Effects of Heat Treatment on the Microstructure and Hardness of A356 (AlSi7Mg0.3) Manufactured by Vertical Centrifugal Casting

Applied Sciences

Changwook Ji¹  Eunkyung Lee²  Wonho Kim²  Kyungsu Jang³ 

[1] Advanced Forming Process R&D Group, Korea Institute of Industrial Technology (KITECH), Ulsan 44776, Korea;Department of Ocean Advanced Materials Convergence Engineering, Korea Maritime and Ocean University, Busan 49112, Korea;H/W Development, S-FAC Solution Factory, Daejeon 34025, Korea;

关键词: A356 alloys;    centrifugal casting;    hardness;    microstructure;    heat treatment;   

DOI  :  10.3390/app112311572

来源: DOAJ

【 摘 要 】

The A356 alloy has been widely used in automotive components, such as wheels and brake disks, because it is an excellent lightweight material with high corrosion resistance and good mechanical properties. Recently, to reduce the weight of brake disks, the Fe-A356 hybrid brake disk has been suggested. Because brake disk quality is directly related to driving safety, the T4/T6 heat treatment of centrifugally cast A356 alloys were performed to enhance the mechanical properties and reduce micro-segregation. The solid-solution heat treatment followed by annealing caused the formation of Mg-rich intermetallic compounds on the grain boundaries of the Al matrix, decreasing the average hardness of the alloys by 13 HV. In contrast, the solid solution followed by water quenching (T4) reduced the area fractions of the intermetallic compounds and increased the average hardness by 11 HV. The T6 heat-treated A356 alloys, which were influenced by the formation of the Guinier–Preston zone exhibited a relatively higher average hardness, by 18 HV, compared to T4 heat-treated A356 alloys.

【 授权许可】

Unknown