Transformation of M/A Constituents during Tempering and Its Effects on Impact Toughness of Weld Metals for X80 Hot Bends release_ki2vzrklpjdljenzzup3pv7kvi

by Gui-ying Qiao, Xiu-lin Han, Xiao-wei Chen, Xu Wang, Bo Liao, Furen Xiao

Published in Advances in Materials Science and Engineering by Hindawi Limited.

2019   Volume 2019, p1-10

Abstract

Impact toughness of the weld metal is one of the important factors affecting the quality of hot bends, which is strongly dependent on the microstructure transformation during hot bending and tempering. In this study, three kinds of weld metals with different Ni contents were selected, and then the effects of tempering temperature on the microstructure impact toughness of weld metals for hot bends were investigated by simulation conducted on a Gleeble-3500 thermal simulator. The results show that the nonmetallic inclusion particles in weld metals can become the nuclear core of acicular ferrite like in as-welded metal. So, the overlapping acicular ferrite microstructure is obtained in the weld metal after direct cooling from the reheating temperature. During tempering, the overlapping acicular ferrite microstructure is degenerated, and martensite/austenite (M/A) constituents in the acicular ferrite microstructure decompose into ferrites and carbides. The resulting carbide particles mainly distribute along the acicular ferrite grain boundaries. With the increase of the tempering temperature, the carbide particles coarsen, which decreases the impact toughness of the weld metal of hot bends. Addition of Ni to weld metals can refine the acicular ferrite and improve the impact toughness.
In application/xml+jats format

Archived Files and Locations

application/pdf   15.1 MB
file_avck5aulczawbcx7v5oumc6voa
web.archive.org (webarchive)
pdfs.semanticscholar.org (aggregator)
web.archive.org (webarchive)
downloads.hindawi.com (publisher)
Read Archived PDF
Preserved and Accessible
Type  article-journal
Stage   published
Date   2019-07-17
Language   en ?
Container Metadata
Open Access Publication
In DOAJ
In Keepers Registry
ISSN-L:  1687-8434
Work Entity
access all versions, variants, and formats of this works (eg, pre-prints)
Catalog Record
Revision: fc52352d-069b-46c7-8fb0-eb4fe602a300
API URL: JSON