The Study Of New Nickle-Ceramic Alloy And The Combination Of Ceramic To Metal

This study is aimed on a new Be-free Nickle-Ceramic alloy. With more reasonable elementary composition of Nickle alloy which suppose to reach basic characteristics of ceramic alloy. Try to avid the useness of harmful elements such as Be which are a complete in present alloys.Using the modern dental laboratory technique to test the characteristics serviceability function and the combination of ceramic to metal, provide the basic knowledge for the clinical use of this new Nickle-ceramic alloy in future material and methods.By different chemical composition materials, vacuum smelt and product different sort of Nickle-ceramic alloys. The strength, hardness, plasticity and castability ratio of the alloy were examined by metal tensile test, grid casting examination and the stick and disk test respectively. The micro structure of the Nickle-alloy are also inspected by using scanning electron microscope and X-ray diffraction analyze. Lastly, using modern dental techniques to make clinical product to check up new type Nickle-ceramic alloys beauty and strength. The alloy are composed of Ni-Cr-Mo solid solution as basement and about 5₈% inter-metal compound. Mo, Cr and Al are all strong solution strengthening element, while Al is also precipitation hardening element which introduces dispersed Y precipitated phase to obviously harden basement. This structure brings mechanical property as excellent as corresponding product both internal and external.Micro-analysis on Nickle-ceramic interface shows that combination between metal and ceramic are tight and simonized in each other without any crack and bubble. The oxidizing layerbetween metal and ceramics is about lum, which stands in the most suitable thickness of 0.2²|jm. Elements disperse and form chemical compound, in which Cr dispersing from metal to interface while Al and Si from ceramics to interface and lastly, forming dispersing layer which brings excellent combination property.The results of choose the new type Nickle ceramic alloy -DA7-18, which elementary composition is base elements of Ni ; Cr 10-25wt%, Mo 5-10wt%, Si 0.2-2wt%, Al 0.2-lwt% and rare elements. The casting function and combination of ceramic to metal function can fulfill the clinical demands. The result of stick and disk test is 36.97 Mpa, higher than VB2 alloy in USA(30.1Mpa). DA7-18 alloy is the yield strength of alloy is 680Mpa, the tensile strength is 780Mpa, the coefficient of expansion is 4%.In a conclusion, the DA7-18 can fulfill the ceramic alloy's demands. Dental technical and design is simple. Marginal strength is good. Be-free Nickle-ceramic alloy also reached the objects of experiment.