A micromechanical model for high strain rate behavior of ceramics

摘要: A constitutive model applicable to brittle materials such as ceramics subjected biaxial compressive loading is developed. The based on non-interacting sliding microcracks that are uniformly distributed in the material. Tension cracks nucleate and propagate from tip of direction maximum applied compression when stress-intensity factor reaches its critical value. For high strain rate deformation, crack growth governed by a universal relation dynamic fracture. provides components for plane deformation which consists an elastic part due tension cracks. failure material linked density damage hence length used study behavior under uniaxial constant loading. beyond would exhibit sensitivity proposed. predicts or peak strength increase with increasing rate. engineering ceramics, exponent found be function between toughness predictions compared rate-dependent hot pressed aluminum nitride tested range 5 × 10^(−6)−2 10^3 s^(−1).