Influence of nickel on mechanical and slurry erosive wear behaviour of permanent moulded toughened austempered ductile iron

摘要

This paper presents a study on the role of nickel content on the slurry erosive wear, strength and impact toughness behaviour of permanent moulded toughened austempered ductile iron (PMTADI) samples subjected to a special austempering heat treatment. The nickel additions were made at five levels ranging from 0.5 to 2.5% in steps of 0.5%. Toughened ADI samples have shown an increase in slurry wear and impact toughness and a slight reduction in tensile strength than samples subjected to conventional austempering heat treatment. The results indicate that there is a significant improvement in slurry erosion resistance for 2.0% nickel PMTADI samples. Samples containing 2.0% nickel shows superior slurry erosion and impact toughness than samples containing either 1% or 2.5% nickel content. The retained austenite content, distribution of bainite and the matrix microstructure play a vital role on the slurry erosive wear and mechanical properties of PMTADI samples.