Showing papers by "Patrick S. Nicholson published in 1973"

Fracture Toughness of a Partially Stabilized ZrO2 in the System CaO‐ZrO2

Abstract: The room-temperature fracture behavior of partially stabilized ZrO3 (PSZ) in the system CaO-ZrO2 was investigated Fracture energy was measured using standard single-edge-crack and work-of-fracture techniques Attempts were made to relate the fracture toughness parameters to the microstructure of the material Stable crack propagation was always observed; a model is proposed to explain these observations on the basis of the formation of a microcrack zone at the tip of a propagating crack The occurrence of initial stable crack propagation is explained in terms of an increase in microcrack zone size The possibility that crack stability results from testing geometry superimposed on the microcracking stability is also discussed

Fracture toughness of a partially stabilized ZrO$sub 2$ in the system CaO-- ZrO$sub 2$

Abstract: The room-temperature fracture behavior of partially stabilized ZrO/sub 2/ (PSZ) in the system CaO-- ZrO/sub 2/ was investigated. Fracture energy was measured using stsndard single-edge-crack and work-of-fracture techniques. Attempts were made to relate the fracture toughness parameters to the microstructure of the material. Stable crack propagation was always observed; a model is proposed to explain these observati ons on the basis of the formati on of a microcrack zone at the tip of a propagating crack. The occurrence of initial stable crack propagation is explained in terms of an increase in microcrack zone size. The possibility that crack stability results from testing geometry superimposed on the microcracking stability is also discussed. (auth)