Creep Deformation Property and Creep Life Evaluation of Super304H
- 8 October 2021
- journal article
- research article
- Published by ASME International in Journal of Pressure Vessel Technology
- Vol. 144 (2)
- https://doi.org/10.1115/1.4052397
Abstract
Creep deformation behavior, creep strength property, and microstructural evolution during creep exposure were investigated on Super 304H steel for boiler tube. In the high stress and lower temperature regime, creep rupture strength of Super 304H steel is higher than that of SUS304H steel. The slope of stress versus time to rupture curve of Super 304H steel, however, becomes steeper with increase in creep exposure time and temperature, and the creep rupture strength of Super 304H steel becomes closer to that of SUS304H steel after the tens of thousands of hours at 700 °C and above. In the short-term, at 600 °C, creep rupture ductility increases with increase in creep rupture life. However, it tends to decrease after showing the maximum value and the creep rupture ductility decreases with increase in temperature. The complex shape of creep rate versus time curves, with two minima in creep rate, was observed at 600 °C. Several type precipitates of niobium carbonitride (Nb(C,N)), Z phase (NbCrN), and copper were observed in Super 304H steel, as well as M23C6 carbide and sigma phase observed in SUS304H steel. The change in slope of stress versus time to rupture curve is caused by disappearance of precipitation strengthening effect during creep exposure. Accuracy of creep rupture life evaluation was improved by stress range splitting method which takes into accounts of the change in slope of stress versus time to rupture curves was demonstrated.Keywords
This publication has 9 references indexed in Scilit:
- Internal Pressure Creep Damage of KA-SUS304J1HTBJournal of the Society of Materials Science, Japan, 2019
- Microstructure of a Heat-Resistant Austenitic Steel after Long-Term Use as Ultra-Supercritical Boiler TubeJournal of the Society of Materials Science, Japan, 2018
- Computer simulation of the yield strength evolution in Cu-precipitation strengthened ferritic steelMaterials Science and Engineering: A, 2010
- A new approach to creep data assessmentMaterials Science and Engineering: A, 2009
- A new methodology for analysis of creep and creep fracture data for 9–12% chromium steelsInternational Materials Reviews, 2008
- Influence of Stress on Degradation and Life Prediction of High Strength Ferritic SteelsPublished by ASME International ,2004
- Effect of Minor Elements on the Long-Term Creep Rupture Time of SUS 304 HTB Stainless SteelJournal of the Japan Institute of Metals and Materials, 2002
- Advances in Physical Metallurgy and Processing of Steels. History of Power Plants and Progress in Heat Resistant Steels.ISIJ International, 2001
- Precipitation Hardening in Fe-Cu Binary and Quaternary Alloys.ISIJ International, 1994