【摘要】 背景:激光选区熔化技术制作的钴铬烤瓷合金正被广泛应用于牙科修复领域,但目前该工艺对钴铬烤瓷合金金瓷结合性能的影响存在争议。目的:观察牙科用激光选区熔化钴铬烤瓷合金金瓷结合界面的特性。方法:分别采用精密铸造法与激光选区熔化法制备钴铬烤瓷合金试件,烤瓷后利用万能试验机、扫描电镜、能谱仪、金相显微镜等方法观察其金瓷结合强度、显微组织、结合界面特性及断裂行为。结果与结论:①精密铸造钴铬合金的金瓷结合强度大于激光选区熔化钴铬合金(P <0.05);②金相显微镜显示,激光选区熔化钴铬合金具有细小的晶粒和较均匀的基体,精密铸造钴铬合金显示了典型的铸造树枝晶组织,具有粗大的晶粒,粗大的晶粒中具有大量岛状的第二相组织;③扫描电镜显示,精密铸造钴铬合金的金瓷反应扩散层厚于激光选区熔化钴铬合金;④扫描电镜显示,精密铸造钴铬合金烤瓷件偏向于内聚断裂,激光选区熔化钴铬合金烤瓷件偏向于黏附断裂;⑤结果表明,激光选区熔化钴铬烤瓷合金的金瓷结合强度虽低于精密铸造钴铬合金,但仍能满足标准YY0621.1-2016的金瓷结合强度要求。更多还原

【Abstract】 BACKGROUND: Co-Cr ceramic alloys made by selective laser melting technology are widely used in the field of dental restoration, but the influence of selective laser melting technology on the bonding properties of Co-Cr ceramic alloys is still controversial. OBJECTIVE: To explore the metal-ceramic interface characteristics of dental Co-Cr alloy fabricated by selective laser melting. METHODS: Metal-ceramic specimens were prepared by selective laser melting and precision casting, respectively. Metal-ceramic bond strengths, interface characteristics, fracture analysis, microstructures and composition distribution of specimens were obtained with the aid of universal testing machine, metallographic microscope, scanning electron microscope coupled with energy disperse spectrometer. RESULTS AND CONCLUSION:(1) The metal-ceramic bond strengths of precision casting Co-Cr alloy was higher than that of selective laser melting Co-Cr alloy(P < 0.05).(2) Metallographic microscope showed that selective laser melting Co-Cr alloy had fine grains and a more uniform matrix. Precision casting Co-Cr alloy showed typical casting dendritic structure with coarse grains and a large number of island second phase structures.(3) Scanning electron microscopy showed that precision casting Co-Cr alloy had a thicker diffusion layer than the selective laser melting Co-Cr alloy at the metal-ceramic interface.(4) Scanning electron microscopy showed that the metal-ceramic specimens of precision casting Co-Cr alloy tended to cohesive fracture, and the metal-ceramic specimens of selective laser melting Co-Cr alloy tended to adhesive fracture.(5) The results showed that although the bonding strength of selective laser melting CoCr alloy was lower than that of precision casting Co-Cr alloy, the bonding strength of selective laser melting Co-Cr alloy could still meet the requirements of standard YY0621.1-2016.更多还原