| About this Abstract |
| Meeting |
MS&T23: Materials Science & Technology
|
| Symposium
|
Light Metal Technology
|
| Presentation Title |
Effect of Melt Thermal-rate Treatment on Microstructure and Mechanical Properties in Al-Zn-Mg-Cu Alloy Billets Fabricated by Direct-chill Casting |
| Author(s) |
Byung-joo Kim, Young-Hee Cho, Hyun-Seok Cheon, Jisu Kim, Su-Hyeon Kim |
| On-Site Speaker (Planned) |
Byung-joo Kim |
| Abstract Scope |
This study investigates the effects of melt thermal-rate treatment (MTRT) on the microstructure and mechanical properties of Al-Zn-Mg-Cu alloy billets fabricated using direct-chill (DC) casting. MTRT was found to enhance the uniformity of solute distribution of Al matrix, leading to improved mechanical properties such as hardness, tensile strength, and ductility. The yield strength, ultimate tensile strength, and elongation in the near-surface region of the billet increased significantly following MTRT. Twinned dendritic grains (TDGs) formed in the central region of the billet, exhibiting a growth advantage during DC casting with MTRT. The uniform solute distribution and the presence of fine, homogeneous intermetallic compounds (IMCs) led to improved mechanical properties compared to non-MTRT billets. However, the elongation of TDGs in the central region was reduced due to microcracks along the TDG boundaries. In conclusion, MTRT shows potential for enhancing the microstructure and mechanical properties of Al alloys produced through DC casting. |