Thermal effect of plastic dissipation at the crack tip on the stress intensity factor under cyclic loading

Nicolas Ranc (1) , Thierry Palin-Luc (2) , Paul Paris (2)

1 PIMM - Laboratoire Procédés et Ingénierie en Mécanique et Matériaux
2 I2M - Institut de Mécanique et d'Ingénierie de Bordeaux

Plastic dissipation at the crack tip under cyclic loading is responsible for the creation of an heterogeneous temperature field around the crack tip. A thermomechanical model is proposed in this paper for the theoretical problem of an infinite plate with a semi-infinite through crack under mode I cyclic loading both in plane stress or in plane strain condition. It is assumed that the heat source is located in the reverse cyclic plastic zone. The proposed analytical solution of the thermo-mechanical problem shows that the crack tip is under compression due to thermal stresses coming from the heterogeneous stress field around the crack tip. The effect of this stress field on the stress intensity factor (its maximum and its range) is calculated analytically for the infinite plate and by finite element analysis. The heat flux within the reverse cyclic plastic zone is the key parameter to quantify the effect of dissipation at the crack tip on the stress intensity factor

Mots clés: Plastic dissipation; Reverse cyclic plastic zone; Stress intensity factor; Thermal stress

Domaines: Génie mécanique [physics.class-ph]; Génie mécanique [physics.class-ph]; Mécanique des structures [physics.class-ph]; Mécanique des structures [physics.class-ph]

Nicolas Ranc, Thierry Palin-Luc, Paul Paris. Thermal effect of plastic dissipation at the crack tip on the stress intensity factor under cyclic loading. Engineering Fracture Mechanics, 2011, 78 (6), pp.961-972. ⟨10.1016/j.engfracmech.2010.11.010⟩. ⟨hal-01057941⟩