Comparison of the Low Temperature Degradation Properties of two Y-TZP Ceramics for Dental Applications
The purpose of this study was to investigate the influence of in vitro low-temperature degradation (LTD) treatments on the structural stability and mechanical properties of two commercial Y-TZP ceramics candidate for dental application. TZ-3YS and TZ-3YS-E powder were chosen because of there minor differences of chemical composition. The two powders were compacted at 200MPa using cold isostatic pressure, and densely sintered at 1500℃ and 1450℃ for 2hr respectively. Two methods of in vitro LTD treatments were performed, the first is to autoclave specimens in steam at 134℃, 2bar, for 1 to 5hr; the second is to immerse specimens into 4% acetic acid at 80℃ for 168 hr. XRD was used to identify the crystal phases, flexural strength were tested according to ISO 6872 standard, surface microstructure was evaluated by Atomic Force Microscopy (AFM). Results show that the relative content of monoclinic phase was increasing with the prolonged aging time, the TZ-3YS was more sensitive to LTD compared with TZ-3YS-E. LTD tests did not necessary reduce the flexural strength of Y-TZP ceramics, the nucleation and growth of monoclinic phase were detected by AFM, and the surface microstructure induced by LTD was not identical between the two Y-TZP ceramics. AFM was a sensitive method to evaluate the transformation of Y-TZP ceramics. To choose appropriate Y-TZP powder for dental application, it is mandatory to examine the microstructure before and after LTD.
Yuanfu Yi Ning Wen Xiaoling Wang Longquan Shao Chen Wang
Department of the stomatology, The General Hospital of Chinese Peoples Armed Police Forces, Beijing Department of the prosthodontics, The General Hospital of Chinese PLA, Beijing 100853,China Department of Stomatology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China The State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University, Beijing 100084, C
国际会议
长沙
英文
107-111
2011-06-30（万方平台首次上网日期，不代表论文的发表时间）