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A discrete dislocation technique for fatigue microcracks (Part I)

  • Vinko Močilnik and Nenad Gubeljak
Published/Copyright: May 16, 2018
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Materials Testing
From the journal Materials Testing Volume 57 Issue 1

Abstract

The present contribution in two continuations summarizes the contents and findings from the latest articles in the field of numerical modeling of initiation and the propagation of micro-cracks within crystalline material by the method of discrete dislocations. The discrete nature of the phenomenon of crack initiation in the crystal grain lattice, the fatigue crack propagation within the crystalline grains and theinfluence of the vicinity of the grain boundary on its propagation and its arrest were discussed, respectively. In accordance with the method of discrete dislocations, an explanation of the reasons for lifetime increase of torsion subjected specimens was provided. The lifetime of the specimens was increased by means of pre-stress compression in axial direction.

Kurzfassung

Der vorliegende Beitrag mit zwei weiteren Fortsetzungen fasst die Inhalte und Erkenntnisse der neuesten Artikel zur numerischen Modellierung der Initiierung und der Ausbreitung von Mikrorissen im kristallinen Material mit Hilfe der Methode der diskreten Versetzungen zusammen. Die diskrete Natur der Rissbildung im Kristallgitter, die Ermüdungsrissausbreitung innerhalb der kristallinen Körner und der Einfluss der Korngrenzenumgebung auf Rissfortschritt und -stillstand wird behandelt. 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.

*Correspondence Address, Prof. Dr. Nenad Gubeljak, University of Maribor, Faculty of Mechanical Engineering, Smetanova ul. 17, 2000 Maribor, Slovenia, E-mail:

Dr. Vinko Močilnik, was born in 1962. He graduated in 1986 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 for 18 years as a development engineer in the field of development and production of technological equipment for metallurgical industry. His main research areas are fatigue and fracture testing and 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. He graduated 1988 at University of Maribor, Faculty of Mechanical Engineering, Slovenia as BSc He continued study at same faculty and completed as PhD in 1998. He spent as a guest researcher a year at GKKS Research Centre Geesthacht in Germany in 2000–2001. He is employed as Head of Institute of Mechanics and Chair of Mechanics at Faculty of Mechanical Engineering at University of Maribor. His main research areas are fatigue and fracture testing, analysis of fracture behavior of welded joints and structure integrity assessment.

References

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Published Online: 2018-05-16
Published in Print: 2015-01-05

© 2015, Carl Hanser Verlag, München

Articles in the same Issue

  1. Inhalt/Contents
  2. Inhalt
  3. Fachbeiträge/Technical Contributions
  4. A simple procedure for estimating SN-lines for crack initiation from SN-lines for total failure*
  5. Modellbasierte Korrelation zwischen dem elektrischen Widerstand und der Versetzungsstruktur des ermüdungsbeanspruchten ICE-Radstahls R7
  6. Effect of cobalt on the aging kinetics and the properties of a CuCoNiBe alloy
  7. Effect of heat treatment on microstructure and mechanical properties of Fe-5Cr-1.4B alloy
  8. Interface characterization of friction welded low carbon steel and copper alloys
  9. Field test methods for aluminum gas cylinders
  10. Application of the Taguchi method for parameter optimization of the surface grinding process
  11. A discrete dislocation technique for fatigue microcracks (Part I)
  12. A discrete dislocation technique for fatigue microcracks (Part II)
  13. Synchrotron X-ray CT of rose peduncles – evaluation of tissue damage by radiation*
  14. Surface roughness analysis and optimization for the CNC milling process by the desirability function combined with the response surface methodology
  15. Design, manufacture and analysis of composite epoxy material with embedded silicon carbide (SiC) and alumina (Al2O3) nanoparticles/fibers
  16. Performance of organic and inorganic substances as inhibitors for chloride-induced corrosion in concrete
  17. Fillet welding of austenitic stainless steel using the double channel shielding gas method with cored wire
  18. Applying quadraphonic transmission ultrasonic defectoscopy on standard aluminum materials
  19. Kalender/Calendar
  20. Kalender
https://doi.org/10.3139/120.110677

Articles in the same Issue

  1. Inhalt/Contents
  2. Inhalt
  3. Fachbeiträge/Technical Contributions
  4. A simple procedure for estimating SN-lines for crack initiation from SN-lines for total failure*
  5. Modellbasierte Korrelation zwischen dem elektrischen Widerstand und der Versetzungsstruktur des ermüdungsbeanspruchten ICE-Radstahls R7
  6. Effect of cobalt on the aging kinetics and the properties of a CuCoNiBe alloy
  7. Effect of heat treatment on microstructure and mechanical properties of Fe-5Cr-1.4B alloy
  8. Interface characterization of friction welded low carbon steel and copper alloys
  9. Field test methods for aluminum gas cylinders
  10. Application of the Taguchi method for parameter optimization of the surface grinding process
  11. A discrete dislocation technique for fatigue microcracks (Part I)
  12. A discrete dislocation technique for fatigue microcracks (Part II)
  13. Synchrotron X-ray CT of rose peduncles – evaluation of tissue damage by radiation*
  14. Surface roughness analysis and optimization for the CNC milling process by the desirability function combined with the response surface methodology
  15. Design, manufacture and analysis of composite epoxy material with embedded silicon carbide (SiC) and alumina (Al2O3) nanoparticles/fibers
  16. Performance of organic and inorganic substances as inhibitors for chloride-induced corrosion in concrete
  17. Fillet welding of austenitic stainless steel using the double channel shielding gas method with cored wire
  18. Applying quadraphonic transmission ultrasonic defectoscopy on standard aluminum materials
  19. Kalender/Calendar
  20. Kalender
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