Fatigue Crack Propagation in Transformation-Toughened Zirconia Ceramic
نویسندگان
چکیده
Fatigue crack propagation under tension-tension loading is observed in ( I trunsjormcition-tougheried purtiully stabilized zirconia (PSZ) certimic wnt~iining 9 mol% M g O . Such subcritical crack p m v t h behavior is clernonstrciterl to be licully induced, based on u comparison with behuvior unrler ,sirstciinerl loading (ut the maximum loud in thejiitigue cycle) and at varying c~clic~,fi-riluciii~ies. Cruck e.rtension rates, Mhich are meanrred US a ,fLi 11 of' the iy. l ic stress intensit? rrmge AK over the range lK'" to 10 mi e , are jixiird to bc. load rutio dependent and to sliow evidence of jatigue crack closure, siniilur to behalior in metals. CFcIic crack growth rates Lire observed 01 AK levels as I O N , NS 3 MPu-m' ' rind are typically muny orders of magnitude fuster tlian reported datu on rnvironqro with in PSZ uriclcr siista inedloud mentally assisted. subcritii~nl L rack conrlitions.
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