Experimental Investigations of Mechanical Characteristics and Tribological Mechanisms of Nanometric Zirconia Dental Ceramics
Changhe Li*, 1, Zhanrui Liu1, Guoyu Liu2, Yucheng Ding1
Identifiers and Pagination:Year: 2011
First Page: 178
Last Page: 183
Publisher Id: TOMSJ-5-178
Article History:Received Date: 26/3/2011
Revision Received Date: 25/5/2011
Acceptance Date: 21/6/2011
Electronic publication date: 27/8/2011
Collection year: 2011
open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: https://creativecommons.org/licenses/by/4.0/legalcode. This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
This study was focused on the experimental investigations about mechanical characteristics and tribological mechanisms of nanometric zirconia dental ceramics. A universal mechanical testing machine was used to test the threepoint flexural strength and the fracture toughness. A microhardness tester was used to test the Vickers hardness of the test specimens. An MRH-3 digital-display high-speed ring-on-block tribometer was used for frictional wear experiments. A PGI800 coarseness profiling instrument was used to test the width and the length of the grinding defects on specimen surfaces. An S-3500N SEM was employed in the microscopic observation of the surface morphology after the abrasion. Results indicates that the flexural strength of the test specimens ≥ 890MPa, the fracture toughness ≥6Mpa.m1/2, the Vickers hardness ≥ 1240MPa, the linear contraction ≥ 21%, and the apparent porosity ≥ 0.32%. Moreover, the frictional factor and the wear rate of nanometric ZrO2 ceramics decreased significantly under identical working and frictional conditions compared with ZrO2. The wear mechanism of nanometric ZrO2 ceramics was micromachining and plastic deformation while the wearing mechanism of ZrO2 ceramics was brittle fracture and abrasive wear.