Crack growth resistance of Al2O3-ZrO2(nano) (12 mol% CeO2) ceramics

• Autorzy: Szutkowska M. , Boniecki M.
• Języki publikacji: EN

Abstrakty

EN

Purpose: Alumina-zirconia ceramics with nano 12 mol% CeO2 stabilized ZrO2 were presented as new ceramics with improvement fracture behavior: better crack growth resistance and limited susceptibility to slow crack growth. This ceramics exhibits good cutting properties. Design/methodology/approach: The controlled crack growth of specimens with double notch was carried with using Zwick testing machine. The specimens with double notch were loaded with rate of 1micrometre min to the -1. The loading of the specimens has been broken at the moment of crack propagation. The procedure has been repeated many times up to obtaining definite increase of crack length. In situ observation of crack growth from notch up to failure was possible due to special device with microscopical objective heads in vertical configuration coupled with CCD camera fitted to Zwick 1446 testing machine. A load-relaxation technique method was used for determination a relationship of a crack growth velocity (v) versus stress intensity factor (KI) and calculation the parameters of SCG. Findings: Many newly developed ceramics that are designed for high-temperature applications or electronic devices possess a low crack growth resistance. It is a drawback in widely usage of these materials in industry. Application of the ZrO2nano stabilized with 12 mol% CeO2 in alumina-zirconia ceramics improves the fracture toughness and decreases the susceptibility to slow crack growth in comparison to pure alumina ceramics. Observation of the controlled crack growth in the tested ceramics reveals the existence of increasing R-curve in the alumina-zirconia ceramics with nano ceria stabilized zirconia. Practical implications: Due to improvement of fracture behavior of the alumina-zirconia ceramics with nano12 mol% CeO2 stabilized ZrO2 could be used in "dry cutting" machining. Originality/value: A combination of in situ microscopic long-through thickness crack growth observation during three point bending (3PB) of a single edge notched beam (SENB) enabled measurement of the R-curve. In presented work a new load relaxation method was worked out for determination susceptibility tested ceramics to slow crack growth.

Słowa kluczowe

EN

ductility; crack resistance; fracture toughness; R-curve; slow crack growth

PL

ciągliwość; odporność na pękanie; odporność na kruche pękanie; krzywa R; wzrost pęknięć; powolny wzrost pęknięć

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2007
• Tom: Vol. 22, nr 1
• Strony: 41--44
• Opis fizyczny: Bibligr. 12 poz., rys., tab.

Twórcy

autor

Szutkowska M.

autor

Boniecki M.

• Materials Engineering Department, Institute of Advanced Manufacturing Technology, ul. Wrocławska 37 a, 30-011 Kraków, Poland,

Bibliografia

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