Mechanoluminescent SrAl2O4:Eu,Dy phosphor for use in visualization of quasidynamic crack propagation

The propagation of a macroscale crack was visualized in Mg partially stabilized zirconia ceramic using the mechanoluminescence (ML) of SrAl2O4:Eu,Dy⁠. The transformation zone around the crack was also clearly detected by the ML. The ML technique permitted on a relatively fast time frame the quasidynamic R curve to be measured for crack speeds up to 15m∕s⁠. The transformation zone width grew to a maximum in the initial transient part of the quasidynamic R curve. The applied stress intensity factor then commenced to increase to 16MPam⁠.