The Influence of Austenite Grain Size on the Mechanical Properties of Low-Alloy Steel with Boron

Abstract

This study forms part of the current research on modern steel groups with higher resistance to abrasive wear. In order to reduce the intensity of wear processes, and also to minimize their impact, the immediate priority seems to be a search for a correlation between the chemical composition and structure of these materials and their properties. In this paper, the correlation between prior austenite grain size, martensite packets and the mechanical properties were researched. The growth of austenite grains is an important factor in the analysis of the microstructure, as the grain size has an effect on the kinetics of phase transformation. The microstructure, however, is closely related to the mechanical properties of the material such as yield strength, tensile strength, elongation and impact strength, as well as morphology of occurred fracture. During the study, the mechanical properties were tested and a tendency to brittle fracture was analysed. The studies show big differences of the analysed parameters depending on the applied heat treatment, which should provide guidance to users to specific applications of this type of steel.

Effect of Welding Process on Microstructural and Mechanical Characteristics of Hardox 600 Steel

“…This is additionally motivated by the adverse opinion about the weldability of this steel, which generally results in resignation of its welding or in replacing it by another grade with lower strength, but declared better weldability. On the grounds of the results of numerous own research works related to chemical and structural properties of low-alloy martensitic steels [29][30][31][32][33][34][35][36][37], it can be generally stated that Hardox steels (mostly 400, 450, and 500 grades) show good weldability, as additionally confirmed by their position in the C-CEV diagram (Figure 1) in the area of low (I) or dependent on welding conditions (II) susceptibility to cracking. However, higher grades of this steel (e.g., Extreme) and the analysed Hardox 600 do not seem to confirm this statement (see Table 3 and Figure 1).…”

Combined Effect of Phosphorus Grain Boundary Segregation, Yield Strength, and Grain Size on Embrittlement of a Cr–Mo Low‐Alloy Steel

“…The steel samples were austenitized at different temperatures (960–1150 °C) and then oil quenched, followed by tempering for 2 h at 650 °C to attain a unified microstructure. The austenitization at different temperatures aimed to obtain different prior austenite grain sizes so as to explore the grain size effect on embrittlement . The average grain sizes were determined by the linear intercept method with metallographic observations .…”

Micro-Texture Analyses of a Cold-Work Tool Steel for Additive Manufacturing

“…Although the prior austenite grain boundaries are not obvious in the final martensitic microstructures, it is generally accepted that the prior austenitic grain size contributes significantly to mechanical properties [40]. Additionally, in the correlation with process conditions at high temperatures, it can be more informative than the sizes of the martensitic subunits (such as lath, plate, packet, and block).…”