Creep deformation effects on the mechanical properties of a silicon nitride ceramic

In the present work, Si3N4 specimens were deformed in creep conditions. The uniaxial plastic deformation induced by creep affected more the standard deviation of the flexural strength than the mean values. No influence was found for the hardness in the compressive zone, while in the tensile zone a hardness reduction was measured after a certain amount of plastic deformation. The apparent Young modulus revealed that, after creep deformation, some anisotropy can be introduced in the originally isotropic material.