Creep behavior of a large full-size welded austenitic steel plate
- CEA-CEREM, Gif-sur-Yvette (France). Service de Recherches Metallurgiques Appliquees
- INSA-Rennes (France). Dept. Genie Mecanique et Automatique
The high-temperature design codes are presently considering the use of stress reduction factors for designing welded structures submitted to creep. These reduction factors are derived from creep tests which are generally made on small specimens and are not necessarily representative of large-size geometries. These codes are very likely overconservative, consequently uneconomical and need to be improved; an investigation to assess and quantify the supposed size effect is required. This paper presents an experimental and numerical study on creep behavior at 600 C of full-size welded joints taking into account real full-thickness of weldings. The material investigated is the austenitic stainless steel 316L(N) with manual metal arc welds using the 19 Cr 12 Ni 2 Mo electrode grade. The creep laws used in calculations are those obtained from tests using small specimens, but some coefficients of their theoretical formulation have been modified to obtain a better coherence with full-size specimen data. Between small and large full-size specimens, experimental results show no significant difference in time to rupture, and the same location of fracture, at the center of the weldment, is observed. Finite element simulations performed for full-size welded joints provide rupture times that are consistent with measured values. The calculated percentage of the damaged volume in the weld metal as a function of load levels and of creep-time duration is studied; it shows that the creep-rupture times for high stress loading are determined with higher accuracy than for low stress loading.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 655473
- Journal Information:
- Journal of Pressure Vessel Technology, Vol. 120, Issue 3; Other Information: PBD: Aug 1998
- Country of Publication:
- United States
- Language:
- English
Similar Records
Microstructure and creep characteristics of dissimilar T91/TP316H martensitic/austenitic welded joint with Ni-based weld metal
Creep crack growth in a Type 316 austenitic stainless steel weld metal. Part 1: effects of metallurgical variables and temperature