A discrete dislocation technique for fatigue microcracks (Part III)

Vinko Močilnik; Nenad Gubeljak

doi:10.3139/120.110696

Article

A discrete dislocation technique for fatigue microcracks (Part III)

Vinko Močilnik and Nenad Gubeljak

Published/Copyright: April 14, 2015

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From the journal Materials Testing Volume 57 Issue 3

Abstract

In accordance with the method of discrete dislocations, an explanation of the reasons for the increase in lifetime of torsion subjected specimens is given. The lifetime of the specimens was increased by means of pre-stress compression in the axial direction. The increase in service life of axial pre-stressed mechanical parts fatigued by torsion or a combination of torsion and bending is explained by the method of discrete dislocations, which will be discussed in detail in this study.

Kurzfassung

In Übereinstimmung mit der Methode der diskreten Versetzungen wurden die Gründe für die Lebensdauererhöhung torsionsbeanspruchter Proben ermittelt. Die Lebensdauer der Proben wurde mittels Vorkomprimierung in axialer Richtung erhöht. Die Erhöhung der Lebensdauer der axial vorbeanspruchten Bauteile, ermüdet durch Torsion oder durch Kombination aus Torsion und Biegung, wurde in dieser Studie mittels der Methode der diskreten Versetzungen detailliert diskutiert.

§Correspondence Address, Prof. Dr. Nenad Gubeljak, University of Maribor, Faculty of Mechanical Engineering, Smetanova ul. 17, 2000 Maribor, Slovenia, nenad.gubeljak@um.si

Dr. Vinko Močilnik was born in 1962. In 1986, he graduated from the Faculty of Mechanical Engineering, University of Ljubljana, Slovenia. He continued his postgraduate studies and received his PhD in 2009 at Faculty of Mechanical Engineering, University of Maribor, Slovenia. He worked as a development engineer in the field of development and production of technological equipment for metallurgical industry for eighteen years. His main research areas are fatigue and fracture testing as well as the application of these findings in manufacturing technologies and the development of new products. He is a researcher at the Institute of Mechanics, Faculty of Mechanical Engineering, University of Maribor and a lecturer at the Engineering High School.

Prof. Dr. Nenad Gubeljak was born in 1963. In 1988, he graduated from University of Maribor, Faculty of Mechanical Engineering, Slovenia as BSc. He continued his studies at same faculty and completed his PhD in April 1998. He spent a year (2000–2001) as guest researcher at GKKS Research Centre Geesthacht in Germany. He is Head of the Institute of Mechanics and Chair of Mechanics at the Faculty of Mechanical Engineering, University of Maribor, Slovenia. His main research areas are fatigue and fracture testing, analysis of fracture behavior of welded joints and structure integrity assessment.

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Published Online: 2015-04-14

Published in Print: 2015-03-02

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https://doi.org/10.3139/120.110696