HYDROGEN-INDUCED DELAYED FRACTURE OF ALUMINA CERAMICS

Hydrogen-induced delayed fracture could occur in alumina ceramics during dynamic charging under constant load. The threshold stress intensity factors were KIH=0.71KIC (i=20 mA/cm2) and 0.45KIC(i=400 mA/cm2), respectively. The fracture surface of hydrogen-induced delayed fracture was intergranular, but that of overloading fracture was mixed intergranular and transgranular.