Analysis of heat treatment effect on microstructural features evolution in a micro-alloyed martensitic steel

Abstract

The microstructural evolution of a quenched and tempered medium-C micro-alloyed steel during tempering is analyzed The steel was heat treated in order to develop fully martensitic microstructures after quenching with different prior austenite grain sizes (AGS). Main results are a very poor effect of AGS on packet size is found, as well as, high-angle boundary grains do not significantly grow after tempering; on the contrary, low-angle grain boundaries (cells) move, fully justifying the hardness evolution with tempering temperature.