Non-equivalence contribution of geometrically necessary dislocation and statistically stored dislocation in work-hardened metals

This work reveals the non-equivalence contribution of geometrically necessary dislocation (GND) and statistically stored dislocation (SSD) to work hardening of the dual-phase steel. The high-GND density of the steel was introduced by load-unload-reload (LUR) pre-tensile, while that with high-SSD den...

Full description

Saved in:
Bibliographic Details
Published in:Materials science & engineering. A, Structural materials : properties, microstructure and processing Structural materials : properties, microstructure and processing, 2022-03, Vol.836, p.142728, Article 142728
Main Authors: Wang, Nan, Chen, Yongnan, Wu, Gang, Zhao, Qinyang, Zhang, Zhen, Zhu, Lixia, Luo, Jinheng
Format: Article
Language:English
Subjects:
Dislocation density
Dual phase steels
Equivalence
Geometrically necessary dislocation
Gtatistically stored dislocation
HDI stress
Predeformation
Residual stress
Strain hardening
Work hardening
Yield stress
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:This work reveals the non-equivalence contribution of geometrically necessary dislocation (GND) and statistically stored dislocation (SSD) to work hardening of the dual-phase steel. The high-GND density of the steel was introduced by load-unload-reload (LUR) pre-tensile, while that with high-SSD density are initiated by monotonic pre-tensile. After pre-deformation, the steel with high GND exhibits significantly higher yield stress and stronger strain hardening ability than the high-SSD steel under almost the same total dislocation density. Different from SSD, GND is originated accompanied by long-range internal stress which can produce additional hetero-deformation induced (HDI) stress strengthening. It is further revealed that dislocation hardening produced by GND is stronger in work-hardened metals, and by introducing high-GND density, the strength of the material can be effectively improved in the structure design. [Display omitted] •This work reveals firstly the strengthening contribution caused by GND is not identical with that caused by SSD in work-hardened metals, and the former is stronger.•The contribution model of GND and SSD dislocations to strength is established in work hardening.•Total dislocation density, GND density and SSD density are systematically calculated during the load-unload-reload (LUR) pre-tensile and monotonic pre-tensile.•It provide a new idea for the design of high-strength metals, i.e. introducing high-GND density.
ISSN:0921-5093
1873-4936
DOI:10.1016/j.msea.2022.142728