Journal Article

PUBDB-2025-00233

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Realizing improved strain aging capability in bake-hardenable steel

Gu, G. H.Extern* ; Kim, Y. ; Kwon, H.Extern* ; Lee, J. H.Extern* ; Yi, S. (Corresponding author)Extern* ; Maawad, E.HZG*Hereon* ; Ha, C.Extern* ; Seo, M. H. ; Kim, H. S. (Corresponding author)Extern*XFEL.EU*

2025
Elsevier Amsterdam

This record in other databases:    

Please use a persistent id in citations: doi:10.1016/j.msea.2025.147817

Abstract: It was revealed that heterogeneous microstructures enhance the strain aging capability of bake-hardenable steels. The improved strain aging capability was validated through a quantitative comparison using a single material with identical chemical composition, grain size, and initial dislocation density. Beyond well-known improvements by hetero-deformation induced (HDI) strengthening and hardening, heterostructured low-carbon steel was found to have improved strain aging ability compared to its homogeneous counterpart. The mechanisms underlying enhanced strain aging capability are as follows: The strength enhancement mechanism of heterostructured materials, defined as HDI effect, produces additional geometrically necessary dislocations (GNDs) during plastic deformation. The increased dislocation density in the heterostructured low-carbon steel compared to its homogeneous counterpart (∼ 1.9 X 10^14 m^-2 at 5 % plastic pre-strain) provides additional carbon segregation sites, forming Cottrell atmospheres during subsequent low-temperature heat treatment (200 °C for 20 min). The segregated carbon atoms function as pinning dislocations, and a greater number of pinned dislocations in the heterostructured low-carbon steel necessitates higher stresses for the initiation of plastic deformation. Consequently, the heterostructured low-carbon steel, subjected to the strain aging process with 5 % plastic pre-strain, achieved an improved yield strength over the homogeneous low-carbon steel in the same state, primarily attributed to the contributions of the HDI effect (∼17.14 MPa) and an improved bake hardening response (∼19.37 MPa). These findings uncover additional functionalities of heterostructured low-carbon steels, offering substantial implications that span from fundamental research to industrial applications, particularly due to their enhanced mechanical properties.

Note: Waiting for fulltext

---

Contributing Institute(s):

1. DOOR-User (DOOR ; HAS-User)
2. Helmholtz-Zentrum Hereon (Hereon)

Research Program(s):

1. 6G3 - PETRA III (DESY) (POF4-6G3) (POF4-6G3)

Experiment(s):

1. PETRA Beamline P07 (PETRA III)

Appears in the scientific report 2025

---

Database coverage:
; Clarivate Analytics Master Journal List ; Current Contents - Engineering, Computing and Technology ; Current Contents - Physical, Chemical and Earth Sciences ; Ebsco Academic Search ; Essential Science Indicators ; IF >= 5 ; JCR ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

---