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Investigation of Pitting Mechanism in the FZG Pitting Test
Technical Paper
2003-01-3233
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
Extended gear fatigue pitting life is an essential performance requirement for today's gear oils in automotive driveline applications. One of the important industrial standard tests used to evaluate fully formulated oil's ability to extend gear pitting fatigue life is the FZG pitting test. To understand the fatigue pitting behavior in these gears we have conducted surface analyses on the FZG gears to determine fatigue modes. We have found that micro-pitting is the major fatigue mode and pitting/spalling is mostly initiated by micro-pitting in the FZG test. To help further understand how pitting and micro-pitting relate to gear oil properties and gear surface morphology, we have also carried out a statistical analysis correlating fatigue pitting life with four major physical parameters: boundary friction coefficient, oil film thickness, oil corrosiveness, and surface roughness of the gear tooth. It is found that a model developed based on these four physical parameters is applicable to predicting the fatigue pitting life in the FZG test for both automatic transmission fluids and gear oils.
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Citation
Li, S., Devlin, M., Milner, J., Iyer, R. et al., "Investigation of Pitting Mechanism in the FZG Pitting Test," SAE Technical Paper 2003-01-3233, 2003, https://doi.org/10.4271/2003-01-3233.Also In
References
- Michaelis, K. “Testing Procedures for Gear Lubricants with the FZG Test Rig” Industrial Lubrication and Tribology 91 94 1974
- Winter, H. Weiss, T. “Some Factors Influencing the Pitting, Micro-pitting (Frosted Area) and Slow Speed Wear of Surface Hardened Gears” J. Mech. Design 103 499 505 1981
- Winter, H. Oster, P. “Influence of Lubrication on Pitting and Micro-Pitting Resistance of Gears” Gear Technol. March April 17 23 1990
- Hoehn, R. B. Michaelis K. “Test Methods for Gear Lubricants in the FZG Gear Rig” Balkan Tribol. 4 4 221 231 1998
- Schonnenbeck, G. “Influencing Factors on Grey Staining (Micro-Pitting)” Proceedings of the 11th International Colloquium on Industrial and Automotive Lubrication Technische Akademie Esslingen Ostifildern, Germany January 13-15 425 431 1998
- Anderson, N.E. Lev, L.C. Mordukhovich, G. “Pitting Fatigue in Automotive Planetary Gearsets” JSME International Conference on Motion and Power Transmissions November 15-17 2001
- Mordukhovich, G. Anderson, N. “Lubrication in Helical Gears,” New Horizons for Tribology and Lubricants - Handbook of Tribology and Lubrication 10 Bartz W.J. Expert Verlag 2002
- Cristinacce, M. “Developments in the production of Engineering Steels - The Advantages for Gear Manufacturers from Secondary Steelmaking” Materials and Design 13 1 33 41 1992
- Milbourn, D.J. “Production and Characterization of Steels” Gear Research Council Seminar Hewitt J. Sheffield I. British Gear Research Association 1996
- Halligan, B. “Tertiary Lubricant Additives - Snake Oils or Real Improvers?” Proceedings of the British Gear Association Annual Technical Congress Paper No. 3 1993
- Nixon, H.P. Zantopulos, H. “What the Equipment Design Engineer Needs to Know” Lubr. Eng. 51 10 815 825 1995
- Littmann, W.E. “The Mechanism of Contact Fatigue” Interdisciplinary Approach to the Lubrication of Concentrated Contacts NASA 309 377 1970
- Hoeprich, M.R. “Rolling Element Bearing fatigue Damage Propagation” Trans ASME 114 328 333 1992
- Moyer, C.A. “Comparing Surface Failure Modes in Bearings and Gears: Appearances vs. Mechanisms” AGMA Tech Paper July August 1992 34 42
- Cast Irons ASM Specialty Handbook ASM International Materials Park, Ohio 1996
- Constans, B. Oster Schedl, U. “Influence of Lubricants on the Pitting Life of Automotive Gears (report from the CEC IT-067 uinvestigation group)” 5th International Symposium on the Performance Evaluation of Automotive Fuels and Lubricants May 13 15 1997 Goteborg, Sweden
- Specification for factory fill CVT fluids April 22 2002 ZF Friedrichshafen AG 88038 Friedrichshafen, Germany
- Constans. B. Oster P. Schedl. U. “Influence of Lubricants on the Pitting Life of Automotive Gears - report from the CEC IT-067 investigation group” Fifth CEC International Symposium on the Performance Evaluation of Automotive Fuels and Lubricants” May 13-15 1997 Goteborg, Sweden “Description of the FZG Pitting Test (FZG/C/PT)” FZG Munich Feb. 1997 Sept. 1995
- Johnston, G.J. Wayte, R. Spikes, H.A. “The Measurement and Study of very Thin Lubricant Films in Concentrated Contacts” Tribol. Trans. 34 187 194 1991
- Hamrock, B.J. Dowson, D. “Isothermal Elastohydrodynamic Lubrication of Point Contacts: Part III-Fully Flooded Results” ASME J. Lubr. Technol. 99 2 264 276 1977
- Kim, C. Kuo, C.C. Marchand, D.M. “Development of the Ball Rust Test - A Laboratory Test Replacing the Sequence IID Engine Test” SAE Paper No. 972861 1997
- Kuo, C.C. Marchand, D.M. Lam, W.Y. “The Effects of Oil Additives in the Ball Rust Test” SAE Paper No. 972923 1997
- Brownlee, K.A. Statistical Theory and methodology in Science and Engineering John Wiley and Sons Inc. 1960
- Drago, R.J. Fundamentals of Gear Design Butterworths, Boston 1988
- Shaw, B.A. Evans, J.T. “Micro-Pits under the Microscope” Drives and Controls Conference Kamtech Publishing UK 36 43 1997
- Winer, W.O. Cheng, H.S. “Film Thickness, Contact Stress and Surface Temperatures” Wear Control Handbook Peterson M.B. Winer W.O. ASME New York 81 141 1980
- Errichello, R. “Friction, Lubrication, and Wear of Gears” Friction, Lubrication, and Wear Technology, ASM Handbook 18 ASM International Metals Park, Ohio 535 545 1992
- Blok, H. “The Postulate about the Constancy of Scoring Temperature” Interdisciplinary Approach to the Lubrication of Concentrated Contacts NASA 153 248 1970
- Ueno, T. Ariura, Y. Nakanishi, T. “Surface Durability of case_carburized Gears - on a Phenomenon of “Gray-Staining” of Tooth Surface” Paper No. 80-C2/DET-27 ASME 1 8 1980
- Shaw, B.A. Hofmann, D.A. Evans, J.T. “Identification of Failure Modes in Hardened Gears” Drives and Controls Conference Kamtech Publishing UK 23 30 1998
- Shipley, E.E. “Failure Analysis of Corse-Pitch, Hardened, and Ground Gears” Paper No. P229.26 AGMA 1 4 1982
- Hoeprich, M.R. “Analysis of Micro-Pitting of Prototype Surface Fatigue Test Gears” Tribotest J. 7 4 333 347 2001
- Vernkatesh, V. C. Krishnamurthy, R. “On Some Aspects of Metallurgical Changes During Gear Pitting” Source Book on Gear Design, Technology, and Performance Hoes, M. A. H. Am. Soc. Metals Metal Park, Ohio 224 228 1980
- Morrison, D. C. J. Org. Chem. 23 1072 1074 1958
- Wei, Z. Duley, P. Somasundaran, P. “Pitting Inhibition of Stainless Steel by Surfactants: an Electrochemical and Surface Chemical Approach” J. Colloids Interface Sci. 259 97 102 2003