Bibliographic Details
Title: |
EFFECTS OF TEMPERING AND PWHT ON MICROSTRUCTURES AND MECHANICAL PROPERTIES OF SA508 GR.4N STEEL |
Authors: |
KI-HYOUNG LEE, MYUNG JO JHUNG, MIN-CHUL KIM, BONG-SANG LEE |
Source: |
Nuclear Engineering and Technology, Vol 46, Iss 3, Pp 413-422 (2014) |
Publisher Information: |
Elsevier, 2014. |
Publication Year: |
2014 |
Collection: |
LCC:Nuclear engineering. Atomic power |
Subject Terms: |
Reactor Pressure Vessel, Heat Treatment, Tempering, PWHT, Transition Property, Nuclear engineering. Atomic power, TK9001-9401 |
More Details: |
Presented in this study are the variations of microstructures and mechanical properties with tempering and Post-Weld Heat Treatment (PWHT) conditions for SA508 Gr.4N steel used as Reactor Pressure Vessel (RPV) material. The blocks of model alloy were austenitized at the conventional temperature of 880 °C, then tempered and post-weld heat treated at four different conditions. The hardness and yield strength decrease with increased tempering and PWHT temperatures, but impact toughness is significantly improved, especially in the specimens tempered at 630 °C. The sample tempered at 630 °C with PWHT at 610 °C shows optimum mechanical properties in hardness, strength, and toughness, excluding only the transition property in the low temperature region. The microstructural observation and quantitative analysis of carbide size distribution show that the variations of mechanical properties are caused by the under-tempering and carbide coarsening which occurred during the heat treatment process. The introduction of PWHT results in the deterioration of the ductile-brittle transition property by an increase of coarse carbides controlling cleavage initiation, especially in the tempered state at 630 °C. |
Document Type: |
article |
File Description: |
electronic resource |
Language: |
English |
ISSN: |
1738-5733 |
Relation: |
http://www.sciencedirect.com/science/article/pii/S1738573315301376; https://doaj.org/toc/1738-5733 |
DOI: |
10.5516/NET.07.2013.088 |
Access URL: |
https://doaj.org/article/ed13adbd1e1e451cb3c803af0df61379 |
Accession Number: |
edsdoj.13adbd1e1e451cb3c803af0df61379 |
Database: |
Directory of Open Access Journals |