This paper studies the dynamic fatigue or slow crack growth in piezoelectric ceramics
under electromechanical loading by a combined numerical-experimental approach.
Constant load-rate testing was conducted in three-point flexure using the single-edge
precracked-beam specimens under zero and positive electric fields, and the effects of
electric field and loading-rate on the fracture load and crack propagation were
examined. A finite element analysis was also employed to calculate the energy
release rate for the permeable, impermeable and open crack models, and
the effect of electric field on the energy release rate was discussed. Crack
propagation velocity versus energy release rate curves at various loading-rate
were then estimated based on the finite element analysis using measured
data.
Keywords
elasticity, finite element method, material testing,
piezoelectric materials, dynamic fatigue, smart materials
and structures