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Metallography, Microstructure, and Analysis

, Volume 7, Issue 5, pp 493–503 | Cite as

Improving the Weld Procedure for Aged HP-Mod Alloy Reformer Tubes

  • Kiran Rampat
  • Chris Maharaj
Review
  • 34 Downloads

Abstract

Welding of service-exposed, aged heat-resistant nickel-base alloys is notoriously difficult. There is a high propensity for cracking in the heat-affected zone (HAZ) of the weld which manifests during or immediately after the welding process due to creep induced embrittlement. The cracks due to creep induced embrittlement are typically accelerated by high residual stresses. To minimize this damage mechanism, the original weld procedure was modified from a double-angle V-groove to a U-groove, and a stringer pattern was used instead of weaving at a higher interpass temperature. Welds were prepared and tested using the modified procedure which was beneficial in minimizing the occurrence of fissures and subsequent cracking due to creep induced embrittlement. Comparative hardness testing of the original and modified weld procedures’ revealed a reduced HAZ width with the modified procedure that most likely facilitated the minimization of creep induced embrittlement.

Keywords

HAZ cracking HP-Mod.Nb Reformer tubes Creep induced embrittlement 

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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature and ASM International 2018

Authors and Affiliations

  1. 1.Nutrien Ltd.Point Lisas, CouvaTrinidad and Tobago
  2. 2.Department of Mechanical and Manufacturing EngineeringThe University of the West IndiesSt. AugustineTrinidad and Tobago

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