Defect Formation of Gray Iron Casting

Cast iron is one of the oldest technical alloys (engineered cast materials) used for creating objects. From the very beginning of casting, foundrymen were fighting to avoid casting defects. In the beginning a successfully produced casting was associated with witchcraft. Cast component producers suffer substantial yearly expenses due to rejecting or repairing castings. This present work will summarize research efforts to understand the formation mechanisms of defects, performed in collaboration with Swedish foundries during the last few years. It will focus on defects specific to the casting of gray iron components and the studied defects: gas porosity, shrinkage porosity and metal expansion penetration. Novell experimental set up has been developed or existing methods have been improved to study defect formation mechanisms. Today we can realize that casting without defects is possible only by approaching the defect formation mechanism with multidisciplinary science.