Microstructural and Finite Element Analysis of Creep Failure in Dissimilar Weldment Between 9Cr and 2.25Cr Heat-Resistant Steels

Microstructural analysis and the creep failure mechanism of dissimilar weldment between ASTM A213 T92 (9Cr1.5W0.5MoVNbTi) and T22 (2.25Cr1Mo) heat-resistant steels are reported. The low-Cr part that has high carbon activity shows a depletion of C during postweld heat treatment. In particular, the so...

Full description

Saved in:
Bibliographic Details
Published in:Metallurgical and materials transactions. A, Physical metallurgy and materials science Physical metallurgy and materials science, 2018-11, Vol.49 (11), p.5323-5332
Main Authors: Sung, Hyun Je, Moon, Ji Hyun, Jang, Min Ji, Kim, Hyoung Seop, Kim, Sung-Joon
Format: Article
Language:English
Subjects:
Axial stress
Carbon
Characterization and Evaluation of Materials
Chemistry and Materials Science
Coalescing
Creep (materials)
Failure analysis
Failure mechanisms
Finite element method
Heat affected zone
Heat resistant steels
Heat treating
Materials Science
Mathematical analysis
Mechanical properties
Metallic Materials
Microstructural analysis
Microstructure
Nanoindentation
Nanotechnology
Post-weld heat treatment
Structural Materials
Surfaces and Interfaces
Thin Films
True stress
Weld metal
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:Microstructural analysis and the creep failure mechanism of dissimilar weldment between ASTM A213 T92 (9Cr1.5W0.5MoVNbTi) and T22 (2.25Cr1Mo) heat-resistant steels are reported. The low-Cr part that has high carbon activity shows a depletion of C during postweld heat treatment. In particular, the soft carbon-depleted zone (CDZ) with the lowest hardness is surrounded by strong weld metal (WM) and the T22 heat-affected zone (HAZ). Load-displacement curves obtained by nanoindentation experiments are used to extract true stress–strain curves of the WM, the CDZ, and the T22 HAZ by using finite element methods (FEMs). Because of the mechanical properties of each region, the soft CDZ confined between harder regions is exposed to multiaxial stress. Therefore, creep voids actively form and coalesce in this CDZ and lead to macroscopic brittle fracture.
ISSN:1073-5623
1543-1940
DOI:10.1007/s11661-018-4859-x