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Welding of High Entropy Alloys—
Published in T.S. Srivatsan, Manoj Gupta, High Entropy Alloys, 2020
R. Sokkalingam, K. Sivaprasad, V. Muthupandi
Tensile strength and the ductility of the BMR weld are lowered from the respective base metal. The post-weld heat treatment (PWHT) is one phenomenon which regains the strength of the weld. Since the Cantor alloy could exhibit a single fcc phase in the range of 670–1,280°C, the welds are post-weld heat treated at 800°, 900°, and 1,000°C [68].
NDT (Non-Destructive Testing)
Published in Soosaiya Anthreas, Project Execution of Mega-Projects for the Oil and Gas Industries, 2021
For carrying out NDT on some alloy or special steels or higher thickness carbon steel, PWHT (post-weld heat treatment) is necessary. The PWHT conditions are stated in WPS (Welding Procedure Specifications) and PQR (Procedure Qualification Records) related thereof.
A review of weldability of carbon steel in arc-based welding processes
Published in Cogent Engineering, 2019
Oluwasegun S. Odebiyi, Segun M. Adedayo, Lawal A. Tunji, Martins O. Onuorah
Post weld heat treatment (PWHT) refers to the heat treatments carried out on the weldment after the completion of the welding process. This is to prevent residual stresses and hydrogen present in the weld that can lead to cold cracking which could either be post heating (weldment is not allowed to cool to room temperature) or stress relief (carried out after the weldment had cooled to room temperature). Most carbon steels are susceptible to cold cracking, weld cracking occurs when allowed to cool to room temperature, thus this could be prevented by allowing the hydrogen in the weld pool to diffuse from the weld at some elevated temperatures before the completed weld cools to room temperature, this is called post heating PWHT (Adedayo et al., 2013; Graville, 1973; Hinton & Wiswesser, 2008; Khaled, 2014; Khurmi & Gupta, 1997; Rizvi et al., 2013; Scott Funderburk, 1998).
Assessment of nickel alloy 625 weld overlays deposited by the electroslag process
Published in Welding International, 2018
Soraia Simões Sandes, Camila Pereira Alvarães, Matheus Campolina Mendes, Leonardo Sales de Araújo, Luis Felipe Guimarães de Souza, Jorge Carlos Ferreira Jorge
Weld overlay can be performed by various processes, such as with covered electrodes, MIG/MAG, hollow-wire, TIG, explosive and plasma [2,5,7,9–18]. In some cases post-weld heat treatment (PWHT) is sometimes recommended for relieving residual stresses, lowering the hydrogen content or homogenizing the microstructure [1,9,19]. In this connection, Kahar and Baba Pai [11] comment that the two most productive processes for overlay welding of large components that are subject to corrosion or wear are the submerged-arc and electroslag processes, both using strip electrodes. Although the submerged-arc process (SAW) is used most, electroslag welding (ESW) is recommended when higher productivity and lower degrees of dilution are required. In this connection, Bedi et al. [10] state that the ESW process is more efficient on account of its unique properties, such as high deposition rate, low level of dilution and high-quality deposits. The electroslag process with strip electrodes has found wide application in the surfacing of equipment in the chemical, petrochemical and nuclear industries [19].