Some considerations regarding the fatigue cracks producing pitting wear of gears


  • Claudiu Ovidiu Popa
  • Simion Haragas


fatigue crack, gear, crack nucleation, small length cracks, stresses field, fatigue cracks propagation


In this article some aspects of the fatigue cracks that have the consequence of pitting wear appearance on the spur gears are presented. The main mechanisms leading to the fatigue cracks, crack nucleation, propagation of cracks of small length, as well as the propagation of cracks on long lengths, respectively, will also be analyzed. The stress field, the growth rate as well as the spread of fatigue cracks will be considered.


BILBY, B. A., ESHELBY, J. D., Dislocations and the theory of fracture, Fracture, 1, pp. 99–182, 1968.

BROEK, D., Elementary engineering fracture mechanics, Martinus Nijhoff Publishers, Hague,1984.

CHAN, K.S., LANKFORD, J., A crack tip strain model for the growth of small fatigue cracks, Scripta Metall., 17, 4, pp. 529–532, 1983.

CIOCLOV, D., Fracture Mechanics (in Romanian), Editura Academiei R.S.R., Bucharest, 1977.

CIZELJ, L., SIMONOVSKI, I., Multiscale modeling of short cracks in random polycrystalline aggregates, Materials and Technology, 41, 5, pp. 227–230, 2007.

COLAGELO, V.J., HEISER, F.A., Analysis of metallurgical failures, 2nd Edition, John Wiley and Sons, Inc., 1987.

DAVIDSON, D.L., Characterizing small fatigue cracks in metallic alloys, Metall. and Mat. Transactions A, 35, 1, pp. 7–14, 2004.

GDOUTOS, E.E., Fracture mechanics. An introduction, 2nd Edition, Springer, Dordrecht, 2005.

IRWIN, G. R., Analysis of stresses and strains near the end of a crack traversing a plate, ASME J. of Applied Mechanics, 24, 3, pp. 361–364, 1957.

KHAN, S.M.A., KRAISHEH, M.K., Analysis of mixed mode crack initiation angles under various loading conditions, Engineering Fracture Mechanics, 67, 5, pp. 397–419, 2000.

KONG, X.M., SCHLUTER, N., DAHL, W., Effect of triaxial stress on mixed-mode fracture, Eng. Fracture Mech., 52, 2, pp. 379–388, 1995.

KUDISH, I.I., A New Statistical Model of Contact Fatigue, Tribology Transactions, 43, 4, pp. 711–721, 2000.