Growth of Creep Cavities in 12% Cr Steels
2009 (English)In: Creep & Fracture in High Temperature Components – Design & Life Assessment, 2nd International ECCC Conference, Empa, Dübendorf, Switzerland, 21-23 April, 2009 / [ed] I A Shibli, S R Holdsworth, LANCASTER, PA: DESTECH PUBLICATIONS, INC , 2009, 950-963 p.Conference paper (Refereed)
The nucleation and growth of creep cavities will eventually occupy a considerable fraction ofthe grain boundary. This will lead to microcracks and intergranular fracture thus controllingthe ductility of the component. The traditional approach to predicting this type of failure is tosimulate cavities with only one size. Assumptions of an instant nucleation with symmetricallyplaced cavities make all cavities equally sized. It has been observed, in 12% Cr steels as wellas in other commercial alloys that cavities nucleate during all stages of creep. Creep cavitiesget randomly placed mostly at grain boundaries directed transverse to the loading direction.With continuous nucleation a size distribution of cavities appears, which is compared toobserved average cavity size. Constraints on cavity growth are introduced, which reduces thegrowth rate. This is needed in order to explain the cavity growth of 12% Cr steels.Furthermore, creep rupture will be derived based on the area fraction of cavities, thus explaining the intergranular failure.
Place, publisher, year, edition, pages
LANCASTER, PA: DESTECH PUBLICATIONS, INC , 2009. 950-963 p.
Creep, 12% Cr steels, cavity, growth
IdentifiersURN: urn:nbn:se:kth:diva-12233ISI: 000266610600083ISBN: 978-1-60595-005-1OAI: oai:DiVA.org:kth-12233DiVA: diva2:306591
2nd International Creep Conference Zurich, SWITZERLAND, APR 21-23, 2009
QC 201006162010-03-302010-03-302011-03-07Bibliographically approved