等离子渗氮后纯钛的耐磨性能的研究

目的:模拟口腔环境,研究在牙刷磨耗机的磨擦下,等离子渗氮对纯钛的耐磨性能的影响。方法:铸造纯钛试件24片,随机分为0.2%NaF渗氮组、0.2%NaF未渗氮组、人工唾液渗氮组、人工唾液未渗氮组,在牙刷磨耗机上刷洗75 000次,对比刷洗前后的粗糙度Ra增加值及色彩变化,并在扫描电镜下观察试件表面形貌。结果:与未渗氮组比较,0.2%NaF等离子渗氮后纯钛的表面粗糙度Ra增加值及色彩变化差异均有显著性(P<0.05);不同混合液比较,0.2%NaF溶液对试件的耐磨性能影响较人工唾液的影响大(P<0.05)。SEM观察表明:在0.2%NaF溶液中刷洗后未渗氮组纯钛试件表面磨耗现象严重。结论:等离子渗氮后纯钛的耐磨性能得到提高;含氟溶液能降低纯钛表面的耐磨性能。

The effects of plasma nitriding on the abradability of pure titanium

Objective: To study the effects of plasma nitriding on the abradability of pure titanium in vitro.Methods: 24 cast pure titanium specimens were divided into 4 groups(n=6).In group 1 the samples were treated by plasma nitriding in artificial saliva,in group 2 by plasma nitriding in 0.2% NaF,in group 3 by artificial saliva and in group 4 by 0.2% NaF.The surface roughness(Ra) of the samples was measured before and after brushing for 75 000 times by a tooth brushing machine and observed under SEM.Results: The Ra values were increased by 0.021±0.027,0.022±0.037,0.025±0.015 and 0.046±0.023 in group 1,2,3 and 4 respectively(P<0.05).Less surface attrition was observed in group 1 and 2.Conclusion: Plasma nitriding may increase the abradability of pure titanium.