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http://dx.doi.org/10.5781/JWJ.2016.34.6.47

PWHT Cracking Susceptibility in the Weld Heat-Affected Zone of Reduced Activation Ferritic/Martensitic Steels  

Lee, Jinjong (Ferrous Alloy Department, Advanced Metallic Materials Division, Korea Institute of Materials Science)
Moon, Joonoh (Ferrous Alloy Department, Advanced Metallic Materials Division, Korea Institute of Materials Science)
Lee, Chang-Hoon (Ferrous Alloy Department, Advanced Metallic Materials Division, Korea Institute of Materials Science)
Park, Jun-Young (Ferrous Alloy Department, Advanced Metallic Materials Division, Korea Institute of Materials Science)
LEE, Tae-Ho (Ferrous Alloy Department, Advanced Metallic Materials Division, Korea Institute of Materials Science)
Hong, Hyun-Uk (Department of Material Science and Engineering, Changwon National University)
Cho, Kyung-Mox (Division of Material Science and Engineering, Pusan National University)
Publication Information
Journal of Welding and Joining / v.34, no.6, 2016 , pp. 47-54 More about this Journal
Abstract
Post-Weld Heat Treatment (PWHT) cracking susceptibility in the weld heat-affected zone (HAZ) of reduced activation ferritic-martensitic (RAFM) steels was evaluated through stress-rupture tests. 9Cr-1W based alloys including different C, Ta and Ti content were prepared. The coarse grained heat-affected zone (CGHAZ) samples were simulated with welding condition of 30 kJ/cm heat input. CGHAZ samples consisted of martensite matrix. Stress rupture experiments were carried out using a Gleeble simulator at temperatures of $650-750^{\circ}C$ and at stress levels of 125-550 MPa, corresponding to PWHT condition. The results revealed that PWHT cracking resistance was improved by Ti addition, i.e., Ti contributed to the formation of fine and stable MX precipitates and suppression of coarse M23C6 carbides, resulting in improvement of stress rupture ductility. Meanwhile, rupture strength increased with increasing solute C content.
Keywords
Reduced activation ferritic/martensitic steel; Stress rupture test; Heat-affected zone; Post weld heat treatment;
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Times Cited By KSCI : 1  (Citation Analysis)
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