The main objective of our work is to develop heat treatment technology for commercial tool steels, which leads to the production of nanobainitic or nanomartensitic microstructure with residual austenite and carbides. Due to the unique morphology and phase composition, this microstructure provides high strength and abrasion resistance of the steel in combination with improved toughness and cracking resistance.
Developed technology:
"A method of heat treatment of medium and high-carbon alloyed steels"
The heat treatment technology aims to ensure enhanced fracture toughness and plasticity in tool steels while keeping high hardness, strength and wear resistance. A proposed heat treatment comprising partial bainitization, quenching and tempering has been proposed. It allows obtaining the microstructure of alloyed carbides in a submicron-sized matrix, consisting of bainitic ferrite and tempered martensite, divided by thin films of retained austenite and very fine precipitates of secondary carbides. The high structure refinement and the presence of austenite in filmy morphology ensure significant strengthening of steel and enhancement of fracture toughness due to effective deflection of the crack tip. The proposed technology significantly reduces the risk of quenching deformation.
Due to these advantageous properties, the introduced heat treatment is suitable for application to steel components working under high loads, especially compressive stresses and intense wear conditions.