Metallurgy, Vol. 56 No. 1-2, 2017.
Original scientific paper
Fatigue life of high strength steel for cold forming
R. Ulewicz
; Institute of Production Engineering, Czestochowa University of Technology, Czestochowa, Poland
F. Novy
; Faculty of Mechanical Engineering, University of Zilina, Slovak Republic
Abstract
The article presents the results of fatigue tests carried out on STRENX-type high-strength cold forming steel. For high-cycle fatigue tests carried out using low cycle loading frequencies of around 30 Hz, a ROTOFLEX machine was used. For ultra high-cycle tests, a KAUP-ZU testing machine was employed, which enables fatigue tests to be performed with symetric specimen loading (R = -1) and at a frequency of f ≈ 20 kHz. The relationships σa = f(N) were determined experimentally in the high and ultra high-cycle region for STRENX high-strength steel. To determine the fatigue crack initiation mechanism, the fractographic analysis of fatigue fractures was made.
Keywords
high strength steel; ultra-high-cycle fatigue; Wöhler curve; fractography
Hrčak ID:
168902
URI
Publication date:
2.1.2017.
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