Mechanical Behavior and Corrosion Resisting Property of the Modified Al-Mg-Si Alloy after Hot Forging Process

• Main Authors: Yu-Chih Kao, 高郁智
• Other Authors: 黃和悅
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/fs4vrp

碩士 === 國立虎尾科技大學 === 材料科學與綠色能源工程研究所在職專班 === 100 === The paper describes the effects of microstructure, mechanical behavior and corrosion resisting property via forging, flow forming and heat treatment processes of modified 6061 aluminum alloy containing vanadium as a minor element. The results indicate that the modified alloy can significantly increase ultimate tensile strength, yield strength and hardness in the different parts of aluminum wheel. Because hardness increases and ductility decreases that more easily causes plastic deformation of a modified alloy induces work hardening. Therefore, the severe localized plastic flow causes an average grain size of modified alloy is larger than A6061 alloy. Salt spray test results show that the modified alloy has low corrosion resistance. This is because of the high Cu content in the modified alloy causes an increasing incidence of corrosion damage. The microstructure of A6061 alloy consists of a mixture of Al9Si and Mg2Si precipitates of strengthening phases distributed at cell boundaries. Vanadium forms Al3V precipitates are found around grain boundaries in the modified alloy. Because precipitates may suppress normal grain growth, the modified alloy obtain a finer grain size typically increases tensile strength and hardness but decreases ductility. Keywords：Forging、Flow forming、Work hardening、Grain