Purpose: To investigate the cyclic fatigue damage modes of GI-II glass infiltrated ceramic in Hertzian's contact.
Methods: All ceramic specimens were loaded by a r=3.18 mm WC ball to investigate their cyclic fatigue behavior in Hertzian's contact. Furthermore, the surviving stress was examined by three-point-flexure-test and morphological damages were observed. All statistical analysis were performed with one-way ANOVA. For all tests, a P-value less than 0.05 was considered to be significant.
Results: The strength of the specimens decreased from 395.7+/-46.5MPa to 318.6+/-40.3MPa after the 1st cycle when the load was 900N, 203.6+/-18.7MPa after 10(5) cycles, and 170+/-33.9MPa after 2 x 10(5) cycles. There was significant difference from that of the cycles (P<0.05). According to the loading cycles, the fatigue damage represented bend in loading area, worm-eaten abrasion or exfoliation around loading area and sequent massive exfoliation. But there was not significant different between the 1st cycle and the 105 cycles when the load was 500N.
Conclusion: In Hertzian's contact,the fatigue damage mode is characterized by a quasi-plastic mode caused by crack tip shield and crystal bridging decline which are driven by shear and tensile stress.
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Hua Xi Kou Qiang Yi Xue Za Zhi
February 2009
Dept. of Prosthodontics, School of Stomatology, Tongji University, Shanghai 200072, China.
Objective: To investigate the intensity changes of different thickness ratios of Empress II glass ceramic and GI- II glass-infiltrated alumina ceramic before and after Hertzian contact cyclic fatigue.
Methods: Disk-shaped specimens of different thickness ratios of Empress II glass ceramic and GI-II glass-infiltrated alumina ceramic were respectively fabricated. Hertzian contact technique was imposed on the specimens.
Hua Xi Kou Qiang Yi Xue Za Zhi
April 2007
Dept. of Prosthodontics, Oral Hospital of Tongdi University, Shanghai.
Objective: To compare the difference in strength degradation and morphology damage of two dental ceramic materials after Hertzian contact cyclic fatigue.
Methods: Hertzian contact technique was used to investigate the response of Empress II glass ceramic and GI- II glass-infiltrated alumina ceramic to cyclic fatigue. Critical loads of specimens after different fatigue cycles were recorded.
Hua Xi Kou Qiang Yi Xue Za Zhi
October 2006
Key Laboratory of Oral Biomedical Engineering, Ministry of Education, Sichuan University, Chengdu 610041, China.
Shanghai Kou Qiang Yi Xue
August 2005
Department of Prosthodontics, School of Stomatology, Tongji University, Shanghai 200072, China.
Purpose: To investigate the cyclic fatigue damage modes of GI-II glass infiltrated ceramic in Hertzian's contact.
Methods: All ceramic specimens were loaded by a r=3.18 mm WC ball to investigate their cyclic fatigue behavior in Hertzian's contact.
Hua Xi Kou Qiang Yi Xue Za Zhi
October 2002
West China College of Stomatology, Sichuan University.
Objective: The purposes of this study were to determine the spectral transmittance of GI-II glass/alumina composites and to explore the effects of different specimen thickness and fining arts of glass infiltration on the transmittance. Data were compared with those of Vita In-Ceram Alumina materials.
Methods: Plate-shaped specimens 12.
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