Destructive Mechanism Solution of Aluminum Secondary Ingot 2019-01-1101

Secondary ingot aluminum is used as a material for many automobile parts because it enables to simultaneously reduce weight and lower costs. However, it is unclear whether secondary ingot aluminum is used with an accurate understanding of the material characteristics. This research identified the actual factors in how parts that use secondary ingot aluminum fracture, and examined methods for enhancing the mechanical properties. The relationship between mechanical properties and part strength when secondary ingot aluminum is used in automobile parts was clarified. The fracturing factors of metal material parts were formerly evaluated by two-dimensional microstructure observation and facture surface observation. This research used high-resolution CT to evaluate the microstructure in three dimensions. In-situ observations of fracturing behavior were also made in order to clarify how the shapes of intermetallic compounds in secondary ingot aluminum influence mechanical properties, and methods for enhancing mechanical properties were examined. A study of parts shape using high pressure die-cast parts, which often use secondary ingot aluminum materials, was also carried out to accurately understand the mechanical properties. The results showed that the mechanical properties of the surface layer of the part are crucial for part strength. This shows that design and manufacturing that take the surface layer characteristics of the part into account will enable application of secondary ingot aluminum materials to an even greater range of parts.