Analysis of thermal embrittlement of a low alloy steel weldment using fracture toughness and microstructural investigations
Journal article, 2022

A thermally aged low alloy steel weld metal is investigated in terms of its fracture toughness and microstructural evolution and compared to a reference. The main purpose of the study is to investigate the effects of embrittlement due to thermal ageing on the brittle fracture toughness, and its effects on the influence of loss of crack tip constraint. The comparison of the investigated materials has been made at temperatures that give the same median fracture toughness of the high constraint specimens, ensuring comparability of the low constraint specimens. Ageing appears to enable brittle fracture initiation from grain boundaries besides initiation from second phase particles, making the fracture toughness distribution bimodal. Consequently, this appears to reduce the facture toughness of the low constraint specimens of the aged material as compared to the reference material. The microstructure is investigated at the nano scale using atom probe tomography where nanometer sized Ni-Mn-rich clusters, precipitated during ageing, are found primarily situated on dislocation lines.

Author

M. Boasen

Royal Institute of Technology (KTH)

Kristina Lindgren

Chalmers, Physics, Microstructure Physics

Martin Öberg

Royal Institute of Technology (KTH)

Mattias Thuvander

Chalmers, Physics, Microstructure Physics

Jonas Faleskog

Royal Institute of Technology (KTH)

P. Efsing

Royal Institute of Technology (KTH)

Engineering Fracture Mechanics

0013-7944 (ISSN)

Vol. 262 108248

Subject Categories

Manufacturing, Surface and Joining Technology

Other Materials Engineering

Metallurgy and Metallic Materials

Areas of Advance

Energy

Materials Science

Infrastructure

Chalmers Materials Analysis Laboratory

DOI

10.1016/j.engfracmech.2022.108248

More information

Latest update

3/28/2022