CN102021362A - Multipurpose Ti-Ge series alloy with adjustable property for oral cavity and preparation method thereof - Google Patents

Abstract

The invention provides a multi-purpose Ti-Ge alloy for oral cavity with adjustable performance and a preparation method. Sponge titanium and germanium particles are formulated into an alloy with a designed composition according to a mass ratio of 99-75:1-25, and a Ti-Ge series titanium alloy with uniform composition is prepared by a vacuum non-consumable melting method, and the melting vacuum degree is 0.1- 5×10 ^-4 Pa argon protection, the melting current is 500-1000A, the melting voltage is 10-20V, the alloy ingot is turned over 180° and remelted 3-6 times repeatedly; the above alloy ingot is cast by vacuum differential pressure, and vacuum Suction casting to obtain rods with a diameter of ≡3-10mm. The titanium alloy of the present invention has the characteristics of non-toxicity, adjustable mechanical properties, corrosion resistance, good casting performance, and good biocompatibility. Performance requirements of various dental restoration alloys.

Description

A multi-purpose Ti-Ge alloy for oral cavity with adjustable performance and its preparation method

technical field

The invention relates to a titanium alloy, and the invention also relates to a preparation method of the titanium alloy. Specifically, it relates to a non-toxic medical titanium alloy for oral restoration and a preparation method thereof. the

Background technique

At present, there are 370 million people with tooth loss and defect in my country, 3 billion dental caries, more than 100 million patients need dental implant treatment, and the aging population makes the demand for oral materials more and more. Biomedical metal materials are widely used in the restoration and reconstruction of tooth function loss and orthopedic treatment. Figure 1 summarizes the mechanical properties and uses of typical dental restoration metals currently used clinically. However, Ni-Cr alloys, Co-Cr alloys, Ni-Ti alloys, and Ni and Cr elements in stainless steel have potential carcinogenic effects, which can easily cause human allergic reactions (dry mouth, burning sensation in the mouth, itchy gums, oral mucosal lesions); the cost of Au alloys is high, and the financial burden on patients is heavy. Titanium and titanium alloys have low density (about half of iron-based and cobalt-based alloys), no foreign body sensation when used in the oral cavity, high specific strength, low elastic modulus, good biomechanical properties, biocompatibility, and corrosion resistance Its anti-fatigue performance is better than that of stainless steel and cobalt-based alloys, and it does not change the taste of acidic foods. It has become the most promising medical metal material. However, there are still some deficiencies in the use of titanium and titanium alloys in the dental field. Pure titanium has a high melting point (1667°C), is very active at high temperatures, and is difficult to smelt in dentistry; its tensile strength is low, and its wear resistance is poor. The mechanical strength of removable dentures cannot meet the requirements, and it is used for fixed dentures. Insufficient abrasiveness; in addition, there are problems such as poor rigidity, easy deformation, and difficult processing. The mechanical properties of Ti-6Al-4V alloy can meet the design requirements, but V and Al have strong toxic effects, V mainly affects the enzyme system, Al mainly affects the brain and causes Alzheimer's encephalomyelopathy, and also causes bone loose etc. Casting secondary pure titanium and Ti-6Al-4V alloy are directly used in the design of small parts of implants (such as the connection seam between implant and abutment, the thread of implant, surface micropores, etc.), and their fatigue strength and tensile strength are insufficient , cannot be used clinically. the

An ideal titanium alloy for dental restoration should have the following characteristics: excellent biocompatibility, good strength and plasticity, suitable hardness and good wear resistance, low melting point and excellent casting performance, low density etc. in order to adapt to the specific oral clinical application background and the requirements of dental laboratory manufacturing. At present, a large number of new titanium alloys developed at home and abroad choose Mo, Nb, Zr, Ta, Hf, Pd, Pt and other elements with good biocompatibility as alloying elements. The alloy has a high melting point and a high density. The composition uniformity control of the alloy puts forward higher requirements, especially when it is difficult to cast as a dental material, it is not suitable for use as a dental alloy. A series of new oral titanium alloys have been designed by alloying methods: Ti-Cu, Ti-Ag, Ti-Au, Ti-Co, Ti-Cr, Ti-Zr alloys, etc. Through the retrieval of existing literature, there are reports of titanium and germanium being used in the biomedical field (Chinese Patent Publication No.: CN201285479 and CN201308719), but it is only the mechanical bonding of titanium particles and germanium particles rather than metallurgical bonding; adding a small amount Ge to Nb-based alloys to form superconductors (Kitada, M. (1973). "Superconductivity of Nb-Ti-Ge Alloys." J Jap Inst Metals 37 (1): 104-109. and Kitada, M. and T. Doi(1972). "Applied magnetic Field vs Critical Current Density Characteristics of Superconducting Nb-Ti-Zr and Nb-Ti-Ge Sheets." J Jap Inst Met 36(9):891-896.); In the base alloy, the phase transition temperature can be adjusted to obtain an alloy with shape memory effect (Inamura, T., Y. Fukui, et al. (2005). "Mechanical properties of Ti-Nb biomedical shape memory alloys containing Ge or Ga."Materials Science and Engineering C 25(3): 426-432.); Ti _{99.97～99.93} Ge _0.03～0.07 added with a very small amount of Ge has low-temperature superconductivity (Jian, WB, CYWu, et al. (1996). "Electron- electron interaction and normal-state transport in superconducting Ti-(Sn, Ge)alloys."Physical Review B-Condensed Matter and Materials Physics 54(6): 4289-4292.); In addition, there are a large number of studies on titanium-germanium intermetallic compounds reports. However, the existing technical literature has little research on Ti-Ge alloys. Based on pure titanium, we have developed a series of new Ti-Ge titanium alloys for oral cavity that can meet various purposes by alloying methods. Based on The present invention is now proposed on the basis of our scientific experiments.

Contents of the invention

The purpose of the present invention is to provide a non-toxic, adjustable mechanical properties, corrosion resistance, good casting performance, good biocompatibility and adjustable performance of oral multi-purpose Ti-Ge alloy. The purpose of the present invention is also to provide a multi-purpose Ti-Ge alloy with adjustable performance that can meet the performance requirements of various dental restoration alloys such as crowns, bridges, denture brackets, and implants through the adjustment of the alloy composition. The preparation method of the alloy. the

The purpose of the present invention is achieved like this:

The chemical composition and weight percentage of the performance-adjustable oral multi-purpose Ti-Ge alloy of the present invention are: 1-25% Ge, and the rest are titanium and unavoidable impurity elements. the

The preparation method of multi-purpose Ti-Ge alloy in oral cavity with adjustable performance of the present invention comprises vacuum smelting and differential pressure casting, and the specific steps are:

(1) Sponge titanium with a purity of 99.5-99.9wt% and germanium grains with a purity of 99.5-99.999wt% are formulated into an alloy with a design composition in a mass ratio of 99-75:1-25, and the vacuum non-consumable The smelting method prepares a Ti-Ge series titanium alloy with uniform composition. The smelting vacuum degree is 0.1-5×10 ^-4 Pa, protected by argon gas, the smelting current is 500-1000A, the smelting voltage is 10-20V, and the alloy ingot is turned over 180 °Finally remelt repeatedly 3-6 times;

(2) The above-mentioned alloy ingot is vacuum differential pressure casting, the melting current is 700-800A, and a copper mold and a φ3-5mm hollow graphite rod are used for vacuum suction casting to obtain a rod with a diameter of φ3-10mm. the

The alloy of the present invention is a dental titanium alloy, and for a specific dental application background, the alloy should have good biocompatibility, low melting point and density, and suitable mechanical properties. Based on pure titanium, we select appropriate alloying elements to adjust the properties of the alloy through solid solution strengthening or precipitation strengthening. From the perspective of the entire periodic table, the metal elements that may be used for titanium alloying mainly include Al\Ga\In(IIIA), Ge\Sn(IVA), Cu\Ag\Au(IB), Zn(IIB), Sc \Y\La (IIIB), Ti\Zr\Hf(IVB), V\Nb\Ta(VB), Cr\Mo\W(VIB), Mn(VIIB), Fe\Co\Ni\Ru\Pd\ Os\Ir\Pt (VIII). (1) Considering the biological safety of alloy elements: Be, Al, V, Cr, Co, Ni, Cu, Zn elements have certain toxic and side effects on the human body, and should be avoided in the design of medical titanium alloys; Ti, Zr, Hf, Nb, Ta, Mo, Fe, Pd, Pt, Ge, Au, Sn elements are non-toxic or low-cytotoxic, and are often used in the composition design of new titanium alloys; (2) Considering the melting point and smelting of alloying elements: Zr The melting points of , Hf, Nb, Ta, Mo, Ru, Os, Ir, and Pt are higher than that of Ti. Selecting these elements as alloy elements requires high-power smelting equipment during alloy smelting, and the higher melting temperature is more important for alloy components. The precise control of the system puts forward higher technical requirements. In the design of new titanium alloys, Mn, Cu, Ag, Au, Ga, In, Ge, Sn and other elements with melting points lower than Ti are preferred. (3) Considering the density of alloying elements: the density of Zr, Hf, Nb, Ta, Mo, Ru, Os, Ir, and Pt is higher than that of Ti. If these elements are selected as alloying elements, composition segregation is likely to occur when the alloy is smelted. Alloy composition uniformity control puts forward higher requirements. Considering that the alloy should have a low density, Ge, Ga, and Sn have the lowest densities among low-melting alloy elements. (4) Ge element has certain biological functionality. the

Compared with the prior art, the present invention has the following characteristics: (1) the alloy of the present invention has excellent biological safety for dental restoration and replacement, and some titanium alloys for oral cavity currently being developed, such as Ti-Cu, Ti-Ag , Ti-Co, Ti-Cr alloys contain toxic alloying elements, and there are certain defects in the dental field; (2) the melting point of the alloy is low, and the melting of the alloy is relatively easy; (3) the density of the alloying elements is very low, and the melting of the alloy Composition segregation is not easy to occur, and oral implants made of low-density alloys can reduce the burden on the casting's own weight from the remaining teeth and alveolar ridges in the mouth, which is conducive to the preparation of large-volume maxillary restorations. In addition, the advantages of low density also have technical advantages when firing ceramics on titanium structures, and can fire large-span restorations without thermally induced dimensional shrinkage and without connection; (4) Ge element has good biological effects . GeO ₂ has biological activity, can promote the production of red blood cells, and has a certain therapeutic effect on leukemia; (5) the properties of the alloy can be adjusted by adjusting the content of the alloying element Ge, thus obtaining a Ti-Ge system that can meet different dental applications. alloy.

Description of drawings

Figure 1 is a summary table of dental alloy materials for clinical use;

Fig. 2 is the X-ray diffraction spectrum of Ti-Ge series alloy;

Fig. 3 is the conventional mechanical property of Ti-Ge series alloy;

Fig. 4 is the hardness of Ti-Ge series alloy;

Figure 5a and Figure 5b show the impedance behavior of Ti-Ge alloy in simulated saliva (AS) and fluorine-containing simulated saliva;

Figure 6a and Figure 6b are the potentiodynamic polarization curves of Ti-Ge alloys in simulated saliva (AS) and fluorine-containing simulated saliva;

Figure 7a and Figure 7b are the cytotoxicity evaluation results of Ti-Ge alloys (L929 cells and MG63 cells);

Figure 8 shows the surface cell morphology of Ti-Ge alloys (L929 cells and MG63 cells). the

Detailed ways

The following examples illustrate the present invention further. the

Example 1: Put 58.8 grams of titanium sponge with a mass of 99.7wt% and 1.2 grams of germanium grains with a mass of 99.9wt% into a water-cooled copper crucible in turn, and use a mechanical pump and a molecular pump to pump out the vacuum non-consumable arc melting furnace. Vacuum to 3×10 ^-4 Pa, then rush into 99.999% pure argon, the whole process of melting is protected by argon, using non-consumable tungsten electrode to melt the pre-placed pure titanium after arcing to further remove the vacuum chamber Oxygen, then smelting the alloy of the present invention, smelting current 500A, smelting voltage 10V, after the alloy is completely melted, add electromagnetic stirring for 10s-1min, electromagnetic stirring current 15A, turn the alloy ingot 180° and remelt repeatedly 4 times to obtain an alloy with uniform composition. After testing, the tensile strength of the alloy is 662MPa, the HV is 328, the yield strength is 308MPa, the elongation is 10%, the density is 4.54g/cm ³ , the performance is better than TA2, and it can be used as implant, porcelain crown and bridge and Short bridge fixed dentures.

Example 2: Put 66.5 grams of titanium sponge with a mass of 99.9wt% and 3.5 grams of germanium grains with a mass of 99.99wt% into a water-cooled copper crucible in turn, and use a mechanical pump and a molecular pump to link the vacuum non-consumable arc melting furnace. Vacuumize to 1×10 ^-4 Pa, then rush into 99.999% pure argon, the whole process of melting is protected by argon, using non-consumable tungsten electrode to melt the pre-placed pure titanium after arcing to further remove the Then the alloy of the present invention is smelted with a smelting current of 750A and a smelting voltage of 15V. After the alloy is completely melted, electromagnetic stirring is added for 10s-1min, and the electromagnetic stirring current is 17A. The alloy ingot is turned over 180° and remelted 5 times repeatedly to obtain an alloy with uniform composition. . After testing, the tensile strength of the alloy is 745MPa, the HV is 307, the yield strength is 486MPa, the elongation is 17%, the density is 4.57g/cm ³ , the good mechanical properties are close to Co-Cr alloy, and the ductility is much better than Co-Cr alloy, with excellent corrosion resistance, can be used as removable denture bracket.

Example 3: 54 grams of titanium sponge with a mass of 99.7wt% and 6 grams of germanium grains with a mass of 99.99wt% were placed in a water-cooled copper crucible in turn, and a mechanical pump and a molecular pump were used to link the vacuum non-consumable arc melting furnace. Vacuumize to 1×10 ^-4 Pa, then rush into 99.999% pure argon, the whole process of melting is protected by argon, using non-consumable tungsten electrode to melt the pre-placed pure titanium after arcing to further remove the Then the alloy of the present invention is smelted with a smelting current of 750A and a smelting voltage of 15V. After the alloy is completely melted, electromagnetic stirring is added for 10s-1min, and the electromagnetic stirring current is 17A. The alloy ingot is turned over 180° and remelted 6 times repeatedly to obtain an alloy with uniform composition. . After testing, the tensile strength of the alloy is 716MPa, the HV is 372, the yield strength is 334MPa, the elongation is 5.1%, the density is 4.60g/cm ³ , the mechanical properties are close to type IV Au alloy, and it can be used as an alloy to withstand a large stress. Thin veneer crowns, long bridge fixed and removable dentures.

Example 4: Put 56 grams of titanium sponge with a mass of 99.9wt% and 14 grams of germanium grains with a mass of 99.999wt% into a water-cooled copper crucible in turn, and use a mechanical pump and a molecular pump to link the vacuum non-consumable arc melting furnace. Vacuumize to 3×10 ^-4 Pa, then rush into 99.999% pure argon, the whole process of melting is protected by argon, using non-consumable tungsten electrode to melt the pre-placed pure titanium after the arc is started, to further remove the Then the alloy of the present invention is smelted with a smelting current of 1000A and a smelting voltage of 20V. After the alloy is completely melted, electromagnetic stirring is added for 10s-1min, and the electromagnetic stirring current is 20A. The alloy ingot is turned over 180° and remelted repeatedly 6 times to obtain an alloy with uniform composition. . After testing, the tensile strength of the alloy is 679MPa, the HV is 459, the yield strength is 335MPa, the elongation is 5.5%, the density is 4.70g/cm ³ , the mechanical properties are close to type IV Au alloy, and it can be used for high-stress crowns, Thick veneer crowns, short bridge fixed dentures, etc.

Embodiment 5: 66.5 grams of titanium sponge with a mass of 99.9 wt % and 3.5 grams of germanium grains with a mass of 99.999 wt % were put into a water-cooled copper crucible in sequence, and the melting method was the same as that in Example 2. Then vacuum differential pressure casting is adopted, the melting current is 800A, and a copper mold and a φ4mm hollow graphite rod are used for vacuum suction casting, with a diameter of φ10mm. the

Claims (2)

1. the adjustable oral cavity multi-usage Ti-Ge of performance is an alloy, it is characterized in that its chemical ingredients and weight percentage are: 1-25%Ge, all the other are titanium and unavoidable impurities element.

2. the adjustable oral cavity multi-usage Ti-Ge of performance is the preparation method of alloy, comprises the casting of vacuum melting and pressure reduction, it is characterized in that concrete steps are:

(1) with purity is the titanium sponge of 99.5-99.9wt% and the germanium grain that purity is 99.5-99.999wt%, be mixed with the alloy of design mix in the ratio of mass ratio 99-75: 1-25, adopt vacuum non-consumable melting method to prepare the uniform Ti-Ge series titanium alloy of composition, melting vacuum tightness is 0.1-5 * 10 ^-4Pa, argon shield, the melting electric current is 500-1000A, melting voltage is 10-20V, with remelting 3-6 time repeatedly after 180 ° of the alloy pig upsets;

(2) above-mentioned alloy pig adopts the vacuum differential pressure casting, and fusion current is 700-800A, uses the hollow graphite rod of copper mold and φ 3-5mm to carry out suction pouring and obtains the bar of diameter as φ 3-10mm.

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