Influence of the Mean Load Value in Fatigue Block Loading on Strains

Abstract:

This paper presents the results of the fatigue tests of the specimens made from S3555 steel and aluminum alloy AlCu4MgSi subjected to bending block loading with mean load value. The influence of the changes of the mean load conditions was investigated. During the tests strains were registered and relation between the load and the strains was analyzed. In the case of S355 steel it was observed, that additional hardening occurs when higher value of the mean load is applied at the beginning of the block loading. Other case, when the mean load was increased from zero to maximum, a creep effect of the material was registered. For the specimens made from aluminum alloy similar processes were not observed. The strain levels are almost the same apart from changes of the mean load in load sequence and the fatigue life of the specimens is the same.

• Periodical: Key Engineering Materials (Volume 598)
• Pages: 195-200
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.598.195
• Online since: January 2014
• Authors: Roland Pawliczek*
• Keywords: Block Loading, Fatigue, Hysteresis Loop, Mean Load, Strain

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