Effect of Step Quenching and Zr Addition on the Microstructure and Mechanical Properties of Al-Mg-Si Alloy

• Published in: Korean Journal of Metals and Materials Vol. 52; no. 2; pp. 101 - 111
• Main Authors: Tian, Jian, Woo, Kee Do, Lee, Kwang Jin, Chen, Yuyong
• Format: Journal Article
• Language: English
• Published: 대한금속·재료학회 01.02.2014
• Subjects: 재료공학
• ISSN: 1738-8228; 2288-8241
• DOI: 10.3365/KJMM.2014.52.2.101

The effects of substituting a step quenching process for the traditional water quenching and of adding zirconium into an Al-Mg-Si alloy, were investigated using differential scanning calorimetry (DSC) and transmission electron microscope (TEM), together with a tensile and hardness tester. The results indicated that step quenching and zirconium addition affected the microstructure and mechanical properties significantly. Step quenching at 100 ℃ for the Al-Mg-Si alloy was the optimal choice because it promoted the precipitation of the β′′ phase, afforded the maximum age-hardening response and strength increment, and restrained the negative effect of natural aging. Zirconium addition improved the strength while retaining good plasticity for the precipitation of Al3Zr. Zr partially promoted the precipitation kinetics of the β′′ phase when step quenching was conducted at 50 or 100 ℃. KCI Citation Count: 13