Title

SLOW STRAIN RATE TENSILE TESTS ON HP-40 AUSTENITIC STAINLESS STEEL

SLOW STRAIN RATE TENSILE TESTS ON HP-40 AUSTENITIC STAINLESS STEEL

Authorship

Pérusin, Simon; Peraldi, Raphaëlle; Lacaze, Jacques; Filho, Jader Ferreira Furtado; Andrieu, Eric

DOI

10.5151/2594-5327-0288

Downloads

heading.download_article_detail 104 Downloads

Abstract

HP-40 austenitic stainless steel alloyed with Nb is presently used as material for reformer tubes that are manufactured by centrifugation. The as-cast microstructure consists of a dendritic matrix delineated by a network of NbC and M7C3 carbide types. While this carbide network helps improving creep resistance during normal service, experiments performed during the present study showed it to be detrimental in case of slow strain rate tensile tests at higher temperature. This suggests that this material can hardly support non-uniform loadings such as those building up during temperature overshoots in service. This could possibly explain short term failures of tubes in reforming plants as repeatedly reported in the literature.

 

HP-40 austenitic stainless steel alloyed with Nb is presently used as material for reformer tubes that are manufactured by centrifugation. The as-cast microstructure consists of a dendritic matrix delineated by a network of NbC and M7C3 carbide types. While this carbide network helps improving creep resistance during normal service, experiments performed during the present study showed it to be detrimental in case of slow strain rate tensile tests at higher temperature. This suggests that this material can hardly support non-uniform loadings such as those building up during temperature overshoots in service. This could possibly explain short term failures of tubes in reforming plants as repeatedly reported in the literature.

Keywords

HP-40 stainless steel; Slow strain rate tensile tests; Chromium carbides; Niobium carbides; Cracks

HP-40 stainless steel; Slow strain rate tensile tests; Chromium carbides; Niobium carbides; Cracks