Creep rupture properties of high-temperature bainitic steels after weld repair

Citation
Je. Indacochea et al., Creep rupture properties of high-temperature bainitic steels after weld repair, J ENG MATER, 122(3), 2000, pp. 259-263
Citations number
30
Categorie Soggetti
Material Science & Engineering
Journal title
JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY-TRANSACTIONS OF THE ASME
ISSN journal
00944289 → ACNP
Volume
122
Issue
3
Year of publication
2000
Pages
259 - 263
Database
ISI
SICI code
0094-4289(200007)122:3<259:CRPOHB>2.0.ZU;2-X
Abstract
Welded high-temperature power plant components can experience a greater ris k of failure by creep during service, when compared to similar as-wrought c omponents. The heat-affected zone (HAZ) of alloy steels is usually the regi on of a weldment exhibiting poor mechanical properties. The arc welding of an ASTM A470, Class 8-rotor steel in this study identified the intercritica l heat affected zone (ICHAZ) as the weakest region in terms of creep ruptur e life. The type of welding procedure significantly affects this region, bu t most important are the welding parameters utilized. Because of the micros tructural heterogeneity of the HAZ and sensitivity of these microstructures to changes when exposed to elevated temperatures, their performance at lat er times is difficult to predict. Extrapolation techniques are limited in v alue for predicting service lives of homogeneous materials, because these d o not incorporate the microstructure changes of the materials during high t emperature operation. They are even less useful for predicting the operatin g lives of weldments. This paper considers the creep performance and struct ure stability of the ICHAZ of 12 percent Cr and 21/r-1 Mo vanadium modified weldments produced on a retired CrMo V rotor steel. [S0094-4289(00)00303-0 ].