Improvement of Mechanical Properties and Wear Resistance of Direct‐Quenched Wear‐Resistant Steel by Deformed Austenite

Abstract

Herein, thermomechanically controlled processing (TMCP) and direct‐quenching (DQ) process are investigated to improve the mechanical and wear properties of wear‐resistant steel, compared to the reheating–quenching (RQ) process. Scanning electron microscope, electron backscatter diffraction, transmission electron microscope, and X‐ray diffraction are employed to characterize the microstructures of the DQ and RQ specimens, and the mechanical and wear properties are investigated using the Vickers hardness, impact, tensile, and stirring wear tests for both processes. The results show that DQ steel exhibits strong plasticity, impact toughness, and wear resistance; the DQ process also retains the deformed austenite formed by rolling in the nonrecrystallization region. The compressed austenite reduces the size of the martensite lath and block structure, increases the density and proportion of the high‐angle grain boundaries, and improves the plasticity and toughness of DQ steel. Meanwhile, DQ steel also inherits the high‐density dislocations created during the rolling process, which is its primary strengthening mechanism. The deformed grains in DQ steel reduce the Schmid factor, improve resistance to wear deformation, and enhance its wear performance.

Analysis of abrasive impact wear of a bimetal composite using a newly designed wear testing rig

“…The grain boundary lengths are obtained from the EBSD data using the Aztec Crystal software, and the grain boundary density is calculated by Eq. ( 5) [34].…”

“…Schmid's law states that dislocation slips can be activated when the external stress is higher than the critical shear stress. The critical shear stress is a constant value that is related with the material's crystal structure, and it is the lowest stress for the dislocation to overcome the resistance in a crystal [34]. The Schmid factor (SF) represents the difficulty of dislocation activation and reflects the deformation behaviour of the material.…”

Effect of Coiling Temperature on Microstructures and Precipitates in High-Strength Low-Alloy Pipeline Steel after Heavy Reduction during a Six-Pass Rolling Thermo-Mechanical Controlled Process

“…Based on these requirements, certain heat treatment processes (such as quenched and tempered [11]) and transformation-induced plasticity provide suitable HSLA steels with high strength and toughness [12][13][14][15]. As an effective method, TMCP has been extensively employed to produce HSLA steel [16].…”