Preliminary communication

The use of short crack growth model for service-life estimation of pitting-prone surfaces

Zoran Ren ; University of Maribor, Faculty of Mechanical Engineering Maribor, SLOVENIA
Srečko Glodež ; University of Maribor, Faculty of Mechanical Engineering Maribor, SLOVENIA

Abstract

A computational model for determining the service-life of contacting surfaces in regard to surface pitting of mechanical elements is presented. In view of small crack lengths observed in surface pitting, the simulation takes into account the short fatigue crack growth theory. The model considers the material fatigue process leading to pitting, i.e. the conditions required for the development of pits by simulation of the short fatigue crack propagation originating from the initial crack in a single material grain. Due to general lack of required micromechanical fracture parameters, different assumptions are proposed how to bridge the related shortcomings of the used model. The stress field in the contact area and the required functional relationship between the stress intensity factor and the crack length are determined by the finite element method. An equivalent model of two contacting cylinders is used for numerical simulations of crack propagation in the contact area. The probable service life period of
contacting surfaces is estimated for surface curvatures and loadings that are most commonly encountered in engineering practice on the basis of numerical results considering some particular material parameters.

Keywords

short crack growth model, service-life estimation, pitting-prone surfaces, computational model, fatigue, finite element method, crack propagation, material parameters

Hrčak ID:

318849

URI

https://hrcak.srce.hr/318849

Publication date:

7.12.2000.

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