Growth of long fatigue cracks under non-proportional loadings – experiment and simulation

Published on Jun 13, 2016in Fracture and Structural Integrity
· DOI :10.3221/IGF-ESIS.37.31
Yigiter Hos4
Estimated H-index: 4
(Technische Universität Darmstadt),
Michael Vormwald25
Estimated H-index: 25
(Technische Universität Darmstadt)
Sources
Abstract
An experimental campaign was carried out on thin-walled tubes under tension and torsion. The results from experiments are measured and compared. It is observed that cracks follow a shear-dominated growth pattern with increasing crack length, instead of a tension-dominated one. The experiments are performed with high amplitudes applied to the specimens, resulting in large cyclic plastic deformations and crack growth rates up to 10-3 mm/cycle. Stress intensity factors were calculated for the proportional loading case.
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A series of fatigue experiments on thin-walled tubes under tension and torsion, the experimental results – crack path and crack growth life – are measured and compared. It is observed that the cracks follow a curvature from a tensile to a shear dominated growth with increasing crack length. The results are enforced by the high amplitudes applied to the specimens causing large cyclic plastic deformations and crack growth rates in the order of 10-3 mm/cycle. The non-linear nature of the cyclic def...
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#2Michael Vormwald (Technische Universität Darmstadt)H-Index: 25
Last. José L. F. FreireH-Index: 7
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