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Investigation of the effects of surface roughness and shot peening on the tooth root bending strength of case-carburized gears

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Abstract

Past studies have demonstrated the positive effects of shot peening, superfinishing, and polish grinding on the flank load-carrying capacity of gears. However, there have as yet not been any thorough investigations into the effects of superfinishing or polish grinding with or without prior shot peening on tooth root bending strength. An extensive experimental study was carried out to investigate the effect of various finishing processes on tooth root bending strength and to determine whether the familiar positive effects of shot peening are maintained after such finishing processes. Smooth surfaces due to superfinishing and polish grinding do not significantly influence the tooth root bending strength of case-carburized gears, assuming that other geometric, metallographic and radiographic properties are unaffected. The increased tooth root bending strength of shot peened and superfinished or polish ground gears demonstrates that the positive effect of shot peening is maintained in combination with superfinishing and polish grinding, if compressive residual stresses are present near the surface of the material.

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Abbreviations

Rz :

Mean peak-to-valley roughness

Ra :

Arithmetic mean roughness

Y RrelT :

Relative surface factor

Rt :

Peak-to-valley roughness

N G :

Limit load cycles

z :

Number of teeth

b :

Face width

m n :

Normal modue

σ ES, max :

Maximum of the residual stress depth profile

\({\sigma _{F0\infty ,\,50\,\% }}\) :

Nominal tooth root bending strength for 50 % failure probability

x :

Profile shift coefficient

α n :

Normal pressure angle

β :

Helix angle

Y S :

Stress correction factor

Y F :

Form factor

In :

Surface roughness measurement length

λ c :

Surface roughness cut of filter

CHD 550HV1 :

Case hardening depth for 550 HV1

Ref :

Unprocessed tooth root fillet

GS :

Superfinished tooth root fillet

KS+GS :

Shot peened and superfinished tooth root fillet

BG ref :

Unprocessed tooth root fillet for larger size

BG KS+GS :

Shot peened and superfinished tooth root fillet for larger size

S:

Conventionally ground tooth root fillet

PS :

Polish ground tooth root fillet

KS+PS :

Shot peened and polish ground tooth root fillet

References

  1. J. Zhang and B. A. Shaw, The effect of superfinishing on the contact fatigue of case carburised gears, Applied Mechanics and Materials, 86 (2011) 348–351.

    Article  Google Scholar 

  2. T. Sakurada and M. Kobayashi, Effects of shot peening and grinding on gear strength, SAE Technical Paper 940729 (1994).

  3. J. König, P. Koller, T. Tobie and K. Stahl, Correlation of relevant case properties and the flank load carrying capacity of case-hardened gears, Proceedings of the ASME Design Engineering Technical Conference (2015) V010T11006.

  4. D. Kratzer, J. König, T. Tobie and K. Stahl, Effects of different shot peening treatments in combination with a superfinishing process on the surface durability of case-hardened gears, Proceedings of the 2020 AGMA/ABMA Annual Meeting (2020).

  5. P. Koller, T. Tobie and B.-R. Höhn, Optimized Flank Load-carrying Capacity: Increased Flank Load-carrying Capacity by Combining Shot Peening and Finishing Processes, AiF-Nr. 14908, Research Association for Drive Technology (FVA) (2010) (in German).

  6. D. Kratzer, T. Tobie and K. Stahl, Polish Ground Gears, Load-carrying Capacity and Efficiency Performance of Gears with Smooth Surfaces, IGF-Nr. 20181 N, Research Association for Drive Technology (FVA) (2021) (in German).

  7. R. D. Britton, C. D. Elcoate, M. P. Alanou, H. P. Evans and R. W. Snidle, Effect of surface finish on gear tooth friction, Journal of Tribology, 122(1) (2000) 354–360.

    Article  Google Scholar 

  8. P. Koller, Increased flank load-carrying capacity by optimized residual stresses and surface properties, Doctorial Dissertation, Technical University of Munich, Verlag Dr. Hut. (2013) (in German).

  9. S. Dehbi and K. Hamouda, Improved surface quality by the process of vibratory grinding, Defect and Diffusion Forum, 365 (2015) 183–187.

    Article  Google Scholar 

  10. F. Joachim and N. Kurz, Influence of surface condition and lubricant on tooth flank capacity, International Tribology Colloquium Proceedings: 15th International Colloquium Tribology, Esslingen (2016).

  11. D. Mallipeddi, M. Norell, M. Sosa and L. Nyborg, The effect of manufacturing method and running-in load on the surface integrity of efficiency tested ground, honed and superfinished gears, Tribology International, 131(24) (2019) 277–287.

    Article  Google Scholar 

  12. W. Graf, Polish grinding of gears for higher transmission efficiency, Proceedings of the AGMA Fall Technical Meeting 2015, Detryoit (2016).

  13. E. Brinksmeier, C. Heinzel and N. Bleil, Superfinishing and grind-strengthening with elastic bonding system, Journal of Materials Processing Technology, 209(20) (2009) 6117–6123.

    Article  Google Scholar 

  14. L. Wendt, Current developments in continous generating grinding, Schweizer Schleif-Symposium, Zürich (2016) (in German).

  15. J. König, T. Tobie and K. Stahl, Optimized Flank Load-carrying Capacity II: Load-carrying Capacity of Shot Peened and Superfinished Gear Flanks under Consideration of the Case Properties and the Lubrication Condition, AiF-Nr. 17145, Research Association for Drive Technology (FVA) (2017) (in German).

  16. C. Güntner, T. Tobie and K. Stahl, Influence of the residual stress condition on the load carrying capacity of case hardened gears, AGMA Technical Paper 17FTM20, American Gear Manufacturers Association (2017).

  17. ISO 6336-3:2019, Calculation of Load Capacity of Spur and Helical Gears — Part 3: Calculation of Tooth Bending Strength, International Organization for Standardization (2019).

  18. ISO 6336-5:2016, Calculation of Load Capacity of Spur and Helical Gears — Part 5: Strength and Quality of Materials, International Organization for Standardization (2016).

  19. G. Lechner, Tooth root bending strength of gears with interference fits, Konstruktion im Maschinen-, Apparate und Gerätebau, 19(2) (1967) 41–47.

    Google Scholar 

  20. M. Anzinger, Effects of material and manufacturing on the tooth root bending strength of gears in the regime of finite fatigue life, Doctorial Dissertation, TU München (1991) (in German).

  21. O. Eyercioglu, D. Walton and T. A. Dean, Comparative bending fatigue strength of precision forged spur gears, Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, 211(4) (1997) 293–299.

    Google Scholar 

  22. K. Inoue, T. Maehara, M. Yamanaka and M. Kato, The effect of shot peening on the bending strength of carburized gear teeth, JSME International Journal, Ser. 3: Vibration, Control Engineering, Engineering for Industry, 32(3) (1989) 448–454.

    Google Scholar 

  23. D. Kratzer, F. Dobler, T. Tobie, T. Hoja, M. Steinbacher and K. Stahl, Effects of low-temperature treatments on surface hardness, retained austenite content, residual stress condition and the resulting tooth root bending strength of case-hardened 18CrNiMo7-6 gears, Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, 233(21–22) (2019) 7350–7357.

    Google Scholar 

  24. D. P. Townsend and E. V. Zaretsky, Effect of Shot Peening on Surface Fatigue Life of Carburized and Hardened AISI 9310 Spur Gears, NASA Technical Paper 2047, National Aeronautics and Space Administration (1982).

  25. K. L. Winkler, S. Schurer, T. Tobie and K. Stahl, Investigations on the tooth root bending strength and the fatigue fracture characteristics of case-carburized and shot-peened gears of different sizes, Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, 233(21–22) (2019) 7338–7349.

    Google Scholar 

  26. A. Stenico, Material mechanic investigations the tooth root bending strength of case-hardened gears, Doctorial Dissertation, TU München (2007).

  27. C. Gorla, R. Rosa, E. Conrado and F. Concli, Bending fatigue strength of case carburized and nitrided gear steels for aeronautical applications, International Journal of Applied Engineering Research, 12(21) (2017) 11306–11322.

    Google Scholar 

  28. C. Weber, T. Tobie and K. Stahl, Rapid and precise manufacturing of special involute gears for prototype testing, Proceedings of the AGMA 2019 Fall Technical Meeting, Dctroit (2019).

  29. T. Tobie and P. Matt, Recommendations for the Standardization of Load Capacity Tests on Hardened and Tempered Cylindrical Gears, FVA 563/I, Research Association for Drive Technology (FVA) (2012) (in German).

  30. DIN EN ISO 4288:1998-04, Geometrical Product Specifications (GPS) — Surface Texture: Profile Method — Rules and Procedures for the Assessment of Surface Texture (ISO 4288:1996), Beuth Verlag GmbH, German Institute for Standardization (1998) (in German).

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Acknowledgments

The underlying research work [5, 6] was funded in equal proportions by the Committee of Industrial Research Associations (AiF: Arbeitsgemeinschaft industrieller Forschungsvereinigungen e.V.), the German Federal Ministry of Economics and Technology (BMWi, IGF no. 14908 N and 20181 N) and the Research Association for Drive Technology (FVA: Forschungsvereinigung Antriebstechnik e.V.). The results shown in this work were taken from the FVA research projects: “Optimized Flank Load Carrying Capacity” [5] and “Polish Ground Gears” [6]. More details are available in the final reports.

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Authors and Affiliations

  1. Gear Research Centre (FZG), Technical University of Munich, Garching, Germany

    D. Kratzer, T. Tobie & K. Stahl

  2. BMW AG, Munich, Germany

    P. Koller

Authors
  1. D. Kratzer
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  2. P. Koller
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  3. T. Tobie
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  4. K. Stahl
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Corresponding author

Correspondence to D. Kratzer.

Additional information

Dominik Kratzer has been a research associate at the FZG Gear Research Centre of the Technical University of Munich since 2017. He graduated from the Technical University of Munich with a Master’s degree in Mechanical Engineering. His research focuses on the impact of surface finishing processes and material treatments on the load-carrying capacity of gears.

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Kratzer, D., Koller, P., Tobie, T. et al. Investigation of the effects of surface roughness and shot peening on the tooth root bending strength of case-carburized gears. J Mech Sci Technol 36, 731–740 (2022). https://doi.org/10.1007/s12206-022-0121-y

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  • DOI: https://doi.org/10.1007/s12206-022-0121-y

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