Fatigue crack initiation and growth in a 35CrMo4 steel investigated by infrared thermography

O. Plekhov (1) , Thierry Palin-Luc (2) , Nicolas Saintier (2) , S. Uvarov (1) , O.B. Naimark (1)

1 ICMM - Institute of Continuous Media Mechanics of the RAS
2 I2M - Institut de Mécanique et d'Ingénierie de Bordeaux

The present work is devoted to the investigation of fatigue crack initiation and growth in middle-cycle fatigue (∼105 cycles). Smooth specimens made of 35CrMo4 quenched and tempered steel were loaded in fully reversed plane bending. Temperature field evolution in time was recorded with an infrared camera. The experimental results show that the local heating of metal under fatigue loading is a sensitive and accurate enough manifestation of small fatigue crack initiation. It is shown that the time evolution of the spatial standard deviation of the temperature field can be used to investigate the damage localization and to monitor both the crack initiation and the current location of the fatigue crack tip. This should help to investigate the behaviour of defect during cyclic loading.

Mots clés: crack growth; crack initiation; infrared thermography; middle-cycle fatigue

Domaines: Mécanique des matériaux [physics.class-ph]

O. Plekhov, Thierry Palin-Luc, Nicolas Saintier, S. Uvarov, O.B. Naimark. Fatigue crack initiation and growth in a 35CrMo4 steel investigated by infrared thermography. Fatigue and Fracture of Engineering Materials and Structures, 2005, 28 (1-2), pp.169-178. ⟨10.1111/j.1460-2695.2005.00856.x⟩. ⟨hal-01373473⟩