摘要
目的研究不同人工老化时间对氧化锆表面显微硬度的影响。方法制作20个直径20.0mm、厚度1.0mm的圆盘状氧化锆试件,分级打磨抛光后,按不同老化时间随机分为四组(n=5;A组:0h;B组:5h;C组:10h;D组:15h)在134℃、0.22MPa压力下按分组时间进行人工老化。X射线衍射分析试件表面晶相,计算单斜晶相氧化锆(m-氧化锆)含量。在每个试件上均匀选取12个位点进行显微硬度测量,对数值进行统计学分析。结果 A组试件表面未检测到m-氧化锆,B、C、D试件m-氧化锆含量随老化时间的延长而显著增加(B:5.04%±0.14%;C:8.99%±0.24%;D:15.04%±0.43%)。A、B、C、D四组试件显微硬度值分别为(1390±16)、(1391±22)、(1384±23)、(1370±28)MPa,D组硬度值降低,与A、B、C组差异存在统计学意义(P<0.05)。结论氧化锆材料的低温时效发生量与人工老化时间有相关性;低温时效降低氧化锆表面显微硬度。
Objective To investigate the influence of different artificial time on the surface hardness of zirconia. Methods 20 zirconia specimens in 20.0 mm （diameter） × 1.0 mm （height） were fabricated. After grinded and polished, all specimens were randomly divided into 4 groups （n=5, group A： 0 h; group B： 5 h; group C： 10 h; group D： 15 h） and received different period of artificial aging in autoclave at 134℃ with 0.22 MPa, respectively. After aging, the m phase fraction was determined by X-ray diffraction analysis. Micro-hardness tests were performed at 12 points in each specimen, and then the hardness values were statistically analyzed. Results No m phase was detected in group A. M phase content increased significantly with longer aging time （B： 5.04% ± 0.14%; C： 8.99% ± 0.24%; D： 15.04% ± 0.43%）. The micro-hardness value （MPa） of each group were statistically analyzed （A： 1390 ± 16; B： 1391 ± 22; C： 1384 ± 23; D： 1370 ± 28）, micro-hardness of group D was decreased with statistical significance （P 〈 0.05）. Conclusion The amount of low-temperature degradation of zireonia is related to the time of artificial aging. Low-temperature degradation significantly decreases the surface hardness of zirconia.
出处
《中华口腔医学研究杂志（电子版）》
CAS
2013年第2期21-24,共4页
Chinese Journal of Stomatological Research(Electronic Edition)
基金
广东省科技计划(2011B031300018)
关键词
氧化锆陶瓷
低温时效
人工老化
显微硬度
Zirconia
Low-temperature degradation
Artificial aging
Micro-hardness
