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Objective: titanium its good mechanical properties, corrosion resistance and excellent biocompatibility in the field of medicine is widely used With of oral titanium precision casting technology continues to improve, the titanium in the field of prosthodontics also showed better application prospects. Used in Prosthodontics clinical titanium and Ti-6A1-4V alloy, long-term clinical applications and studies have shown that pure titanium low tensile strength, poor wear resistance, casting, welding, polishing and other processing difficulties defects Ti-6A1-4V process performance, fatigue, and fracture toughness is not ideal and containing Al and V elements, limiting the development of titanium and its alloys in the field of prosthodontics.; Therefore the development of mechanical properties and resistance to corrosion and biocompatibility and easy Prosthodontics fabrication dentures titanium alloys are very necessary to improve the quality of dentures and expanding repair indications. Content method: to repair alloy performance requirements according to the theory of alloy design and d-electron alloy design theory and Dental screening alloying addition to alloy design. Weighing ratio selected raw materials treated according to the design elements, the use of high-vacuum arc melting furnace alloy and aging heat treatment to improve material performance. INSTRON biomechanical testing system (tensile machine), micro hardness tester, optical microscopy, scanning electron microscopy, X-ray diffraction (XRD) analysis instrument analysis investigated alloy elongation, tensile strength, hardness, elastic modulus mechanical properties observe the alloy microstructure, the variation of the elemental composition. Results: 1. This experiment designed alloy component is a Ti-12.5Zr-10Nb-2.5Sn, resulting alloy near α-type titanium alloy. 2. Cooling rate of alloy smelting and metallurgical quality alloys. The experimental alloys prepared by copper crucible quench high vacuum arc melting prepared. Low alloy impurity content, high purity, a smaller loss of alloying elements, resulting alloy and fine grain size, tensile specimen presented toughness fracture, high and tough plastic. Prepare new titanium casting at 580 ℃ for 1-10h aging treatment, the alloy hardness significantly increase the modulus of elasticity with aging time extend generally increasing trend, while the alloy elongation decreased tensile fracture dimples The smaller shallow, gradually increasing brittleness. 4 tissue analysis showed that the alloy with the copper crucible smelting quench the way, the martensitic transformation of metastable α 'phase. In the subsequent aging process, the alloy gradually from the metastable α 'phase transition to the stable α phase. Conclusion: the premise of the biocompatibility principles, choose non-toxic and biological properties of Nb, Zr and Sn were prepared as add elements, design and high-vacuum arc melting method Ti-12.5Zr-10Nb- 2.5Sn near α titanium alloy. Prepared according to the GB sample test results of the mechanical properties, titanium alloy after 4h aging elastic modulus up 126.99GPa, elongation of about 8.3%, tensile strength 848.8MPa, to meet dental repair performance requirements. 2. Titanium alloy phase β, α 'and α equal to a different phase structure alloy can be adjusted through reasonable heat treatment process to meet the performance requirements. 3 smelting using metal copper mold molding, is not conducive to bubble in the discharge of the casting process. Casting blowhole defects will affect the mechanical properties of the alloy elastic modulus. In order to further improve the alloy properties, the need to improve the casting process, the selection or development of a more suitable investment material, preparation of a dense structure of the alloy.
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