Synergy of strengthening and toughening of a Cu-rich precipitate-strengthened steel

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

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Author(s)

  • Xinghao Wei
  • Xue Cao
  • J.H. Luan
  • Z.B. Jiao
  • Z.W. Zhang

Detail(s)

Original languageEnglish
Article number142487
Journal / PublicationMaterials Science and Engineering A
Volume832
Online published10 Dec 2021
Publication statusPublished - 14 Jan 2022

Abstract

A high strength steel with a combination of ∼930 MPa yield strength and excellent low temperature toughness with an upper shelf energy of above 200 J and ductile brittle transition temperature (DBTT) of lower than −90 °C is developed. The strengthening and toughening mechanisms are investigated systematically based on the detailed characterization on microstructures including the matrix and precipitates. The results indicate that the steel is composed of a fine lath martensite with rod-like Cu precipitates. The high strength is achieved by a combination of solid-solution strengthening, dislocation strengthening, grain boundary strengthening and precipitation strengthening of Cu-precipitates. The instrumented Charpy impact results further indicate that the crack propagation is the main factor affecting DBTT while the dislocation density has an obvious effect on both crack initiation and propagation. The fine lath structure of the low carbon martensite enhances the crack resistance and delays the rapid unstable crack propagation at low temperatures. Both the strengthening and toughening are thoroughly discussed in details.

Research Area(s)

  • Crack propagation, Ductile-brittle transition, Impact toughness, Nanoprecipitate-strengthened steel, Strengthening mechanisms

Citation Format(s)

Synergy of strengthening and toughening of a Cu-rich precipitate-strengthened steel. / Wei, Xinghao; Cao, Xue; Luan, J.H.; Jiao, Z.B.; Liu, C.T.; Zhang, Z.W.

In: Materials Science and Engineering A, Vol. 832, 142487, 14.01.2022.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review