Gigacycle fatigue of ultra high density sintered alloy steels

Author(s)
Herbert Danninger, C. Xu, Golta Khatibi, Brigitte Weiss, Björn Lindqvist
Abstract

Sintered steel specimens with density levels of up to 7·6 g cm−3

have been prepared from Cr–Mo and Mo prealloyed powders. The fatigue

response has been studied using an ultrasonic resonance testing device

that enabled testing up to 109 cycles. It showed that the

fatigue endurance strength can be drastically increased by raising the

density and that the sintering conditions are effective, though less

than the density. The existence of a true fatigue limit was disproved up

to 109 cycles for all materials tested, with sintered steels

thus being similar to wrought ones. Cr–Mo steels was shown to be

superior to Mo alloyed grades due to the markedly finer as sintered

microstructure and higher sintering activity. Fatigue crack initiation

was found to originate from pores at first at multiple sites, with

microstructural orientation being dominant compared to the direction of

stress; with progressive loading, some cracks join to form a propagating

macrocrack from which the final failure then starts.

Organisation(s)
Physics of Nanostructured Materials
External organisation(s)
Technische Universität Wien, Höganäs AB
Journal
Powder Metallurgy
Volume
55
Pages
378-387
No. of pages
10
ISSN
0032-5899
DOI
https://doi.org/10.1179/1743290112Y.0000000001
Publication date
2012
Peer reviewed
Yes
Austrian Fields of Science 2012
210006 Nanotechnology, 103018 Materials physics
Portal url
https://ucrisportal.univie.ac.at/en/publications/gigacycle-fatigue-of-ultra-high-density-sintered-alloy-steels(317efaca-c2b7-45fb-bb89-f5a3beba3a47).html