Structure-property relationships in quenched and tempered carbon steels

Abstract

Three carbon steels have been quenched, tempered, cold worked, and then retempered in order to produce microstructures consisting of ferrite grains with carbides at the ferrite grain boundaries or, in the low-carbon steel, large ferrite grains having carbides uniformly distributed within the grains. The microstructural parameters have been determined and related to the Vickers hardpess, the yield stress, and the flow stress at strains of up to 0.1. The results obtained have been analysed in terms of the Hall-Petch relationship to determine the influence of grain size and the Orowan-Ashby relationship to evaluate the influence of dispersed phases. It has been found that ferrite grain size is the major structural parameter controlling the mechanical properties.