冷热循环和人工唾液对Vitallium2000^+钴铬钼合金卡环疲劳强度影响的研究

The effect of temperature cycle and artificial saliva on the fatigue strength of Vitallium2000^+ Co-Cr-Mo alloy clasps

目的探讨冷热循环和人工唾液对Vitallium2000^+钴铬钼合金卡环疲劳强度的影响。方法使用成品卡环蜡型制作Vitallium2000^+钴铬钼卡环21个,随机分为3组,分别置于空气、常温的人工唾液、冷热循环人工唾液溶液中进行测试,自动记录初始载荷强度和疲劳失效前的载荷循环次数,并对疲劳裂纹进行扫描电镜分析。结果 Vitallium2000^+钴铬钼卡环在不同测试条件下的初始载荷强度经比较差异无显著性(P>0.05),在空气中的循环次数最高,在冷热循环人工唾液溶液中的循环次数最低。SPSS分析表明3组之间的疲劳强度差异有显著性(P<0.01)。结论冷热循环和常温下的人工唾液均可使Vitallium2000^+钴铬钼合金卡环的疲劳强度下降。

Objective To study the effect of temperature cycle and artificial saliva on the fatigue strength of Vitallium2000＋ Co-Cr-Mo alloy clasps. Method 21 clasps specimen of Vitallium2000＋ Co-Cr-Mo alloy were made from prefabricated clasp wax, and were divided into 3 groups randomly. Specimens were tested in air, artificial saliva, and artificial saliva with temperature cycle separately. Initial loading force and loading cycle numbers before fracture were registered automatically, and the fracture flaws were examined by a scanning electron microscope （SEM）. Result The initial loading force of Vitallium2000＋ Co-Cr-Mo alloy clasps had no significant difference among three conditions （P〉0.05）. The tested clasps had the highest loading cycle numbers in the air, and the lowest ones in artificial saliva with temperature cycle. Analysis of fatigue strength by SPSS software showed a significant difference among three groups （P〈0 01）. Conclusion Both temperature cycle and artificial saliva reduce the fatigue strength of Vitallium2000＋ Co-Cr-Mo alloy clasps.