Loughborough University
s40194-023-01653-w.pdf (3.11 MB)

Effects of post-weld heat treatment on the microstructure and properties of the matching SMAW filler metal for weld joints in MarBN steel

Download (3.11 MB)
journal contribution
posted on 2024-02-13, 11:19 authored by Zhuyao Zhang, Steve Roberts, Josh Wildgoose, Will Philpott, Mark JepsonMark Jepson

A detailed investigation has been carried out of the matching composition filler metal for welding MarBN steel to explore the influence of welding procedure and post-weld heat treatment (PWHT) on the microstructure and properties of the weld metal and a MarBN steel weld joint. The filler metal was in the form of a shielded metal arc welding (SMAW) electrode. With different interpass temperatures and PWHT procedures applied, the microstructure and mechanical properties, particularly toughness, of the all-weld metal deposits and welded MarBN alloy joints were examined. The differences in microstructure (grain structure, precipitates, etc.) were evaluated to provide a better understanding of how the PWHTs influence the starting conditions of the matching weld metal and welded MarBN steel joints before service. The current work found that for a 30-mm-thick all-weld metal coupon, reasonable impact toughness was achieved after PWHT of 735 °C × 8 h; longer heat treatment durations (16 h and 36 h) did not further increase the toughness. For thicker cast blocks, a PWHT of 735 °C × 16 h was needed for weld toughness comparable to the base metal, hence was considered more appropriate for actual engineering applications. Evenly distributed Laves phase precipitation was observed after 735 °C × 8 h; the precipitates gradually increased in size and area fraction as the duration increased, and appeared to be stable when approaching 36 h. Differences in the precipitation were observed between different weld regions. The weld cap region had a lower density of Laves precipitates compared to the lower weld area. From the current investigation, aspects for further investigation are also identified.


Innovate UK, under Project IMPLANT: “Advanced Materials and Manufacturing for Improved Power and Process Plant Performance”, Innovate UK File Ref. 105769, Jan 2020 – April 2022; and their other project partners: Uniper Technologies Limited, University of Birmingham, ETD Consulting UK

Underpinning Multi-User Equipment

Engineering and Physical Sciences Research Council

Find out more...



  • Aeronautical, Automotive, Chemical and Materials Engineering


  • Materials

Published in

Welding in the World




  • VoR (Version of Record)

Rights holder

© The Author(s)

Publisher statement

This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.

Acceptance date


Publication date


Copyright date







  • en


Dr Mark Jepson. Deposit date: 30 November 2023

Usage metrics

    Loughborough Publications




    Ref. manager