Influence of the Filler Root Surface Treatment on Bending Fatigue Test Results of the Hardened Gears

Abstract:

This article deals with testing of fatigue properties of hardened gears at bending. These tests are defined by the standard ISO 6336 - method B, when testing is carried out under reference conditions close to the real operation. This type of testing may be helpful to evaluate the influence of new materials, design parameters, production technology, or the effects of surface finishing. The first part of this article deals with the theory of fatigue testing methodology using modified stair-case method and characteristics of the testing machine. The second part of the paper is devoted to the characteristics of the experimental material and the results achieved. The case hardened steel gears alloyed by Cr-Ni-Mo were selected for the experiment. Hardened gears were subjected to local hardness measurement and subsequently the bending fatigue tests were performed. Ruptured samples were analyzed using a scanning electron microscope. The local bending stress was determined using the modified computational model based on the ISO 6336 standard methodology. The focus of this work consisted in evaluation of the influence of the filler root surface treatment on fatigue limit at bending on the basis of the realized experiments and their confrontation with the equivalents specified in the standards ISO 6336 and ČSN 01 4686.

• Periodical: Key Engineering Materials (Volume 586)
• Pages: 154-157
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.586.154
• Online since: September 2013
• Authors: Petr Jonšta, Petr Maršálek, Jiří Havlík, Zdenĕk Jonšta
• Keywords: Bending Fatigue Test, Fractographic Analysis, Hardened Gear, Local Hardness, Surface Treatment

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