The effects of metallurgical process variables on the mechanical properties of austempered ductile cast iron

Abstract

The mechanical properties obtained in austempered ductile cast iron are dependent on the metallurgical process variables, namely metal composition and heat-treatment conditions. The investigation of the effects of these metallurgical variables on both the structure and mechanical properties of austempered ductile cast irons are the aim of this thesis. The metallurgical process variables investigated are metal composition, austenitizing temperature, austempering temperature and austempering time. These are listed below. Metal Composition Three different compositions of copper and nickel alloyed ductile cast iron were investigated. The base metal composition was: 3.6% Carbon (C) 2.6% - Silicon (Si) 0.4% max - Manganese (Mn) 0.03% max - Phosphorus (p) 0.03% max - Sulphur (8) Balance Iron (Fe) The base metal was alloyed by copper and nickel to provide the following three different compositions [...].