Damage law identification of a quasi brittle ceramic from a bending test using digital image correlation

Paul Leplay (1, 2, 3) , Julien Réthoré (1) , Sylvain Meille (2) , Marie-Christine Baietto (1)

1 LaMCoS - Laboratoire de Mécanique des Contacts et des Structures [Villeurbanne]
2 MATEIS - Matériaux, ingénierie et science [Villeurbanne]
3 CREE Saint Gobain

Although ceramics are generally considered as to be elastic brittle solids, some of them are quasi brittle. These ceramics show a non linear mechanical behaviour resulting most of the time in a difference between their tensile and compressive stress-strain laws. The characterization of their fracture strengths might be biased if elastic linear formulae are used to analyze classical tests like bending tests. Based on Digital Image Correlation (DIC), an efficient technique to measure full field displacements, a methodology is proposed to characterize and model materials with dissymmetric behaviours between tension and compression. Applying specific basis functions for DIC displacement decompositions for bending, compressive and tensile tests, a stress-strain model and its damage law are identified and then validated for aluminium titanate, a damageable micro cracked ceramic at room temperature. This identification method using DIC can obviously be applied to other quasi brittle materials.

Mots clés: Mechanical properties; Strength; Al2TiO5; Digital Image Correlation

Domaines: Génie mécanique [physics.class-ph]

Paul Leplay, Julien Réthoré, Sylvain Meille, Marie-Christine Baietto. Damage law identification of a quasi brittle ceramic from a bending test using digital image correlation. Journal of the European Ceramic Society, 2010, ⟨10.1016/j.jeurceramsoc.2010.05.021⟩. ⟨hal-00495001⟩