Open Access

ARTICLE

A Finite Element Study of the Influence of Graphite Nodule Characteristics on a Subsurface Crack in a Ductile Cast Iron Matrix under a Contact Load

G. Suguinoshita¹, C. H. Silva¹, M. A. Luersen^{1, *}

1 Department of Mechanical Engineering, Federal University of Technology-Parana (UTFPR), Rua Deputado Heitor Alencar Furtado, 5000, CEP 81280- 340, Curitiba, Brazil.

* Corresponding Author: M. A. Luersen. Email: .

Computer Modeling in Engineering & Sciences 2018, 117(1), 59-71. https://doi.org/10.31614/cmes.2018.01777

Abstract

This paper describes a study of the effects of graphite nodule characteristics on a subsurface crack in austempered ductile iron (ADI). A representative specimen of ADI, subjected to sliding contact load, is modeled using finite elements aiming to obtain the shear stress intensity factor (K_II). The parameters varied were (i) the nodule diameter (two different values were considered), (ii) the distance between the nodule and the tip of the crack and (iii) the position of the load relative to the tip of the crack. The results of the numerical simulations show that the smaller diameter nodule has a larger influence on K_II, suggesting a higher contact fatigue crack propagation rate in the material with the smaller nodule. These results are the opposite of those observed in experimental studies and would appear to indicate that other factors should be also considered to ensure realistic estimates of the contact fatigue strength of ADI.

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Keywords

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