反复熔铸对NEO钴铬烤瓷合金金瓷结合性能的影响

背景：NEO钴铬烤瓷合金不含有害物质,但其钴铬烤瓷合金能否回收利用存在争议,反复熔铸对NEO烤瓷合金性能影响的报道较少。目的：观察反复熔铸对NEO钴铬烤瓷合金金瓷结合力、金相结构、金瓷界面形貌的影响。方法：根据ISO9693标准,采用真空条件下氩气保护加压铸造方法,用三点弯曲实验测试分别经过1~5次熔铸后NEO钴铬烤瓷合金的金瓷结合能力,金相显微镜观察各代铸件金相结构,扫描电镜观察各代试件金瓷结合界面形貌。结果与结论：分别经过1~5次熔铸后的NEO钴铬烤瓷合金的金瓷结合能力差异有显著性意义(P < 0.05);随着熔铸次数增加铸件的树枝状结构和晶粒结构逐渐模糊、消失;试件金瓷界面结合逐渐疏松、过渡层厚度增加。提示经过反复熔铸的NEO会明显影响其金瓷结合性能。 

Effect of recasting on bonding properties of NEO cobalt chromium ceramic alloy

BACKGROUND: NEO cobalt chromium ceramic alloy does not contain harmful substance, but whether it can be reused is still unclear. There are few reports about the effects of recasting on properties of NEO ceramic alloy.OBJECTIVE: To investigate the effects of recasting on bonding properties, metallurgical structure and morphology of metal-ceramic interface of NEO cobalt chromium ceramic alloy.METHODS: The NEO cobalt chromium ceramic alloys were casted by argon pressure casting in vacuum condition according to ISO9693. The bonding properties of NEO cobalt chromium ceramic alloys after recasting for 1-5 times were tested by three-point bending test. Metalloscope was used to observe the metallurgical structures of each generation of casting, and their morphologies of metal-ceramic interface were observed by scanning electron microscope.RESULTS AND CONCLUSION: There were differences in bonding properties of NEO cobalt chromium ceramic alloys after recasting for 1-5 times (P < 0.05). With the increase in recasting time, the dendritic structures and grain structures of castings were gradually blurred and disappeared, the combination of metal-ceramic interface was gradually loosening and the thickness of transition layer was increased. It is indicated that recasting can significantly affect the bonding properties of NEO cobalt chromium ceramic alloy.