2种非贵金属铸造桥循环疲劳破坏的比较实验研究

Comparative study on cracks in cyclic fatigue testing on two types of casting-metal fixed bridge

目的比较不含镍、铍元素的Bego钴铬合金及VB镍铬合金铸造3单位桥在模拟咬合过程中的裂纹萌生及扩展情况。方法常规制作钴铬合金及镍铬合金铸造桥各10组,将制成的铸造桥完全就位于代型后置于疲劳试验机上,模拟不同年限的咬合次数,观测裂纹萌生和扩展情况。结果镍铬合金桥在达疲劳极限时仅观察到裂纹的萌生,而钴铬合金桥在达疲劳极限时未观察到有裂纹生成。结论 Bego钴铬合金在抗疲劳性能上优于VB镍铬合金。

Objective To compare the eruption and elongation of the cracks on casting-metal fixed bridges of cobalt-chromium alloy without glucinium or nickel and nickel-chromium alloy by simulating articulation.Methods Casting-metal fixed bridges of cobalt-chromium alloy and nickel-chromium alloy were made as normal,each group having 10 teams.Put the bridges together with ties on fatigue testing machine,and then the eruption and elongation of the cracks were examined after different articulation times.Results Only eruption of the cracks could be seen when nickel-chromium alloy bridges were loading to fatigue limit,but nothing can be seen on cobalt-chromium alloy ones.Conclusions Cobalt-chromium alloy has better fatigue resistance than nickel-chromium alloy under dynamic cyclic fatigue testing.