Spheroidal Graphite Cast Irons (or Ductile Cast Iron)
The main disadvantage of grey cast irons, regarding the mechanical properties, is the notch effect caused by the flakes of graphite. A model proposed to describe the grey cast irons is a steel with cavities filled with graphite. If this lamellar graphite is transformed into spheroidal graphite, mechanical properties will improve. This chapter is, for that reason, dedicated to the cast irons with spheroidal graphite, and particularly to the austempered ductile irons (ADI). ADI irons are spheroidal graphite cast irons of bainitic matrix with growing interest consequence of the excellent mechanical properties that make them competitive with steels.