How would you characterize a hot tear in an aluminum casting?

A hot tear in an aluminum casting is characterized by a defect that occurs during the cooling process, specifically in complex shapes. This type of defect arises when the metal is still at a relatively high temperature and is not adequately restrained, causing it to develop cracks or tears. These often happen when the metal can’t contract uniformly due to its geometric intricacy or because it has sections of different thicknesses.

Understanding the nature of hot tears is crucial for foundries and metalworking professionals, as they can significantly affect the structural integrity of the castings. This phenomenon often highlights the importance of careful mold design and temperature control during casting processes to mitigate the risk of such defects. While other potential defects exist, hot tears are specifically linked to the internal stresses that arise during the cooling phase of casting, which can result in complex tears that do not necessarily affect just the surface but also the integrity of the entire piece.