Deformational behaviour of ceramics

摘要: The application of modern ceramics, such as cordierite or partially stabilized zircona (PSZ), calls for more detailed data than those provided by conventional investigation strength crack-resistance characteristics. To provide on deformational behaviour (including possible inelasticity), a parameter is proposed in the form ‘brittleness measure’, χ. At χ = 1, ceramic obeys Hooke's law and its mechanical similar to glass. same time, under loading like that concrete it does not correspond elastic-solid model. It has been found aluminium oxide toughened zirconium dioxide yttrium are characterized 1 parameter, while cordierite, silicon nitride with boron nitride, corundum refractory material dioxide, magnesium < 1. It shown that, unlike ceramics retain residual stresses. Being inelastic, they have an ascending R-curve show insignificant differences values critical-stress-intensity factor obtained specimens notch sharp crack. analytical evaluation materials should be based proportionality limits rather ultimate-strength values. Thermal-shock-resistance criteria take into account actual ultimate strains. The presented reveal serviceability, specific features important absolute properties. strains may regarded physicomechanical characteristics this type material.