New classification of defects and imperfections for aluminum alloy castings

In recent years, aluminum alloys have become more and more relevant because of their low density, coupled with good mechanical and corrosion properties. Different processes are available for the production of aluminum alloy components, such as rolling, extrusion, and powder metallurgy, but a significant role is played by foundry processes. Defects and imperfections are physiologically generated by different casting techniques as a result of the process stages, alloy properties and die or mold design. In the present work, a multi-level classification of structural defects and impeifections in Al alloy castings is proposed. The first level distinguishes defects on the basis of their location (internal, external, or geometrical), the second level distinguishes on the basis of their metallurgical origin, while the third level refers to the specific type of defect, because the same metallurgical phenomenon may generate various defects.