Prediction of Microstructure Constituents’ Hardness after the Isothermal Decomposition of Austenite

Abstract

An increase in technical requirements related to the prediction of mechanical properties of steel engineering components requires a deep understanding of relations which exist between microstructure, chemical composition and mechanical properties. This paper is dedicated to the research of the relation between steel hardness with the microstructure, chemical composition and temperature of isothermal decomposition of austenite. When setting the equations for predicting the hardness of microstructure constituents, it was assumed that: (1) The pearlite hardness depends on the carbon content in a steel and on the undercooling below the critical temperature, (2) the martensite hardness depends primarily on its carbon content, (3) the hardness of bainite can be between that of untempered martensite and pearlite in the same steel. The equations for estimation of microstructure constituents’ hardness after the isothermal decomposition of austenite have been proposed. By the comparison of predicted hardness using a mathematical model with experimental results, it can be concluded that hardness of considered low-alloy steels could be successfully predicted by the proposed model.

Physical and Mechanical Characterization Study of Thin Nitriding Layers Produced by Plasma on Low Alloy Steel

“…The second zone shows stationary hardness values for different samples corresponding to the core of the unchanged steel during the treatment. The hardness value of steel core is equal almost of 240 HV0.5N which corresponding to Bainite's hardness according to the literature [15]. Fig.…”

Artificial Neural Networks-Based Prediction of Hardness of Low-Alloy Steels Using Specific Jominy Distance

“…Prediction of mechanical properties is usually based on semi-empirical methods. In [10], the equations for prediction of microstructure constituents' hardness after the isothermal decomposition of austenite are proposed. Developed model can be a very good basis for predicting hardness in continuous steel cooling using Scheil's additivity rule.…”