Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.3/41690

Title

Investigation of cracking mechanisms of plasma sprayed alumina-13% titania by acoustic emission

Author(s)

Lin, Chung Kwei;  Leigh, Sang Ha;  Gansert, Robert V.;  Murakami, Kenji;  Sampath, Sanjay;  Herman, Herbert;  Berndt, Christopher C.

Abstract

Free standing alumina-13% titania samples were manufactured using high power water stabilized plasma spraying. Heat treatment was performed at 1450°C for 24 hours and then at 1100°C for another 24 hours. Four point bend tests were performed on the as-sprayed and heat-treated samples in both cross section and in-plane orientations with in situ acoustic emission monitoring to monitor the cracking during the tests. Catastrophic failure with less evidence of microcracking was observed for as-sprayed samples. Energy and amplitude distributions were examined to discriminated micro- and macro-cracks. It was found that the high energy (> 100) and high amplitude (say > 60 dB) responses can be characterized as macro-cracks. Physical models are proposed to interpret the AE responses under different test conditions so that the cracking mechanisms can be better understood.

Publication type

Conference paper

Source

Materials Research Society Symposium Proceedings: Proceedings of the Fracture: instability dynamics, scaling, and ductile/brittle behavior symposium, Boston, Massachusetts, United States, 27 November-01 December 1995 / Robin L. Blumberg Selinger, John J. Mecholsky, Anders E. Carsson and Edwin R. Fuller Jr (eds.), Vol. 409, pp. 261-266

Publication year

1996

Keyword(s)

Acoustic emissions;  AE;  Alumina;  Amplitude distribution;  Ceramic materials;  Crack initiation;  Energy distribution;  Four point bend tests;  Heat treatment;  High temperature operations;  Macrocracks;  Materials testing;  Mechanical failure;  Microcracks;  Models;  Plasma spraying;  Titanium compounds

Publisher

Materials Research Society

ISSN

0272-9172 (series ISSN)

ISBN

9781558993129, 1558993126

Peer reviewed