Preparation method of high-strength titanium-zirconium alloy wire

Abstract

The invention belongs to the field of medical titanium alloy material processing, and particularly relates to a preparation method of a high-strength titanium-zirconium alloy wire. The Ti-Zr alloy comprises the following chemical components in percentage by mass: 13.5-16.5% of Zr, less than or equal to 0.10% of Fe, less than or equal to 0.10% of C, less than or equal to 0.015% of H, less than or equal to 0.6% of O, less than or equal to 0.05% of N and the balance of Ti. Firstly, a round bar blank with a certain size is obtained through the procedures of smelting, forging and drawing; and then a finished wire is prepared in the modes of temperature-controlled drawing, stress relief annealing and centerless grinding. By means of the method, the high-strength titanium-zirconium alloy wire with Rm larger than or equal to 950 MPa and A larger than or equal to 10% can be obtained, the problems that the implant material Ti-Zr alloy is low in strength and the like are solved, the high-strength titanium-zirconium alloy wire for dental products can be produced through the method, and qualified raw materials are provided for the dental implant products.

Description

Technical Field

[0001] The present invention belongs to the field of processing of titanium alloy materials for medical use, and specifically relates to a method for preparing a high-strength titanium-zirconium alloy wire. Background Art

[0002] Titanium alloys have excellent biocompatibility, corrosion resistance, are non-magnetic and non-toxic, and are widely used in the medical field. Among them, pure titanium materials are widely used in medical dental implant materials. However, pure titanium has insufficient strength, poor wear resistance, and a high risk of stress fatigue, greatly increasing the risk of dental implant failure. In recent years, with the development of the medical and biomedical materials industries, a new type of titanium-zirconium alloy has gradually replaced the original pure titanium materials. However, the strength of the titanium-zirconium alloys produced in China is still relatively low, and the matching of strength and plasticity still cannot meet the requirements of individual medical device manufacturers. Summary of the Invention

[0003] The purpose of the present invention is to provide a method for preparing a high-strength titanium-zirconium alloy wire, to solve the problem of the low strength of the Ti-Zr alloy in the existing implant materials, and to produce a Ti-Zr alloy wire for medical implants with a tensile strength of more than 950 MPa, and the material also has an elongation of more than 10%.

[0004] In order to solve the problem of the low strength of the Ti-Zr alloy, the technical solution adopted by the present invention is as follows:

[0005] A method for preparing a high-strength titanium-zirconium alloy wire, the chemical composition and mass percentage of the Ti-Zr alloy are: Zr is 13.5% - 16.5%, Fe ≤ 0.10%, C ≤ 0.10%, H ≤ 0.015%, O ≤ 0.6%, N ≤ 0.05%, and the balance is Ti;

[0006] The method for preparing the high-strength titanium-zirconium alloy wire includes the following steps:

[0007] Step 1: Prepare a Ti-Zr alloy ingot by vacuum consumable triple melting;

[0008] Step 2: Forge using a quick forging machine and a precision forging machine;

[0009] Step 3: Roll using a tandem rolling mill;

[0010] Step 4: Draw using a disk wire drawing machine;

[0011] Step 5: Straighten using a slider straightening machine;

[0012] Step 6: Anneal the straightened wire;

[0013] Step 7: Centerless grind the wire rod to prepare a wire rod with finished product specifications.

[0014] In the preparation method of the high-strength titanium-zirconium alloy wire rod, in Step 1, sponge titanium, sponge zirconium, and compound TiO2 with a particle size of 3 - 12.7 mm are used, and the materials are proportioned according to the alloy composition, and a vacuum consumable triple melting is adopted to obtain a Ti-Zr alloy ingot.

[0015] In the preparation method of the high-strength titanium-zirconium alloy wire rod, in Step 2, cogging forging is carried out at 950°C - 1050°C for 3 - 6 hours, and finish forging is carried out at 750°C - 850°C for 1.5 - 4.5 hours. During forging, the deformation amount per heat is controlled at 40% - 80%.

[0016] In the preparation method of the high-strength titanium-zirconium alloy wire rod, in Step 3, the rolling temperature is controlled at 750 - 820°C, and heat preservation is carried out for 1 - 2 hours, and the deformation amount per pass is controlled within 15%.

[0017] In the preparation method of the high-strength titanium-zirconium alloy wire rod, in Step 4, the drawing temperature is controlled at 200 - 400°C, the speed of the wire drawing machine is 3 - 5 m / min, and the deformation amount is 30 - 50%.

[0018] In the preparation method of the high-strength titanium-zirconium alloy wire rod, in Step 5, the straightening speed is 1 - 2 m / s.

[0019] In the preparation method of the high-strength titanium-zirconium alloy wire rod, in Step 6, a box-type resistance furnace is selected for annealing, the annealing temperature is 400 - 600°C, and the heat preservation time is 3 - 6 hours.

[0020] In the preparation method of the high-strength titanium-zirconium alloy wire rod, in Step 7, the amount of centerless grinding each time is less than 0.05 mm, and the surface of the finished product is polished.

[0021] The design concept of the present invention is:

[0022] The present invention uses small-particle sponge titanium, sponge zirconium and other alloy materials and compound TiO2, and precisely controls the composition through three times of vacuum consumable melting. The grains are fully refined by controlling the temperature during drawing and adjusting the reasonable deformation amount to improve the strength. At the same time, by means of tension straightening plus stress relief annealing and hyperbolic straightening plus stress relief annealing, the tensile stress and compressive stress in the bar are eliminated, so that it reaches a stress-free state, meeting the requirements for producing medical products.

[0023] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0024] 1. The present invention uses small-particle sponge titanium, sponge zirconium and a small amount of TiO2 as raw materials, and uses a vacuum consumable furnace for three times of melting to ensure the uniformity and consistency of the materials.

[0025] 2. The titanium-zirconium alloy wire produced by the present invention has a tensile strength of more than 950 MPa and an elongation of more than 10%.

[0026] 3. The equipment and processing technology required by the present invention are simple and can meet the needs of mass production. DETAILED DESCRIPTION

[0027] In the specific implementation process, the present invention first obtains a round rod blank of a certain size through smelting, forging and drawing processes; then prepares the finished wire material by temperature-controlled drawing, stress relief annealing and centerless grinding.

[0028] Below, the present invention is further described in conjunction with embodiments.

[0029] Example 1

[0030] In this embodiment, the preparation method of the Ti-Zr alloy wire is as follows:

[0031] Step 1: Use titanium sponge, zirconium sponge and compound TiO2 with a particle size of 3 to 12.7, prepare materials according to the alloy composition, and use vacuum self-consumable melting three times to obtain a Ti-Zr alloy ingot with stable and uniform composition;

[0032] The chemical composition and mass percentage of the Ti-Zr alloy ingot are: Zr is 14.2%, Fe is 0.05%, C is 0.02%, H is 0.013%, O is 0.4%, N is 0.03%, and the balance is Ti.

[0033] Step 2: Use a fast forging machine to keep the temperature at 1000℃ for 4 hours to forge the blank, and use a fine forging machine to keep the temperature at 800℃ for 3 hours to forge. During forging, the deformation amount of each fire is controlled at 60%;

[0034] Step 3: rolling with a horizontal rolling mill, controlling the rolling temperature to 780°C, keeping the temperature for 1.5 hours, and controlling the deformation of each pass to 8%;

[0035] Step 4: Use a disc wire drawing machine to draw, control the drawing temperature to 380°C, the wire drawing machine speed to 4m / min, and the deformation to 41%, to prepare a wire with a specification of Φ5.5mm;

[0036] Step 5: Use a slider straightening machine for straightening at a straightening speed of 1.2 m / s;

[0037] Step 6: Anneal the straightened wire in a box-type resistance furnace at a temperature of 520°C for 4 hours.

[0038] Step 7: Centerless grind the wire material with a centerless grinding amount of 0.03 mm each time, and polish the surface of the wire material to prepare a finished wire material with a specification of Φ5.0 mm.

[0039] Table 1 shows the mechanical property test results of the Φ5.0 mm specification Ti-Zr alloy wire material prepared in Example 1

[0040] Sample number Tensile strength Rm / MPa <![CDATA[Yield strength Rp 0.2 / MPa]]> Elongation A / % Specimen 1 1023 829 16.5 Specimen 2 1022 833 17.0

[0041] Example 2

[0042] In this example, the preparation method of the Ti-Zr alloy wire material is as follows:

[0043] Step 1: Use sponge titanium, sponge zirconium, and compound TiO2 with particle sizes of 3 - 12.7 mm, proportion the materials according to the alloy composition, and perform vacuum consumable melting three times to obtain a Ti-Zr alloy ingot with stable and uniform composition;

[0044] The chemical composition and mass percentage of the Ti-Zr alloy ingot are: Zr is 15.6%, Fe is 0.04%, C is 0.03%, H is 0.010%, O is 0.2%, N is 0.01%, and the balance is Ti.

[0045] Step 2: Use a quick forging machine to perform blooming forging at 980 °C for 3 hours, and use a precision forging machine to perform forging at 760 °C for 2 hours. Control the deformation amount per heat to be 45% during forging;

[0046] Step 3: Use a tandem mill for rolling, control the rolling temperature at 760 °C, keep it warm for 2 hours, and control the deformation amount per pass at 10%;

[0047] Step 4: Use a disk wire drawing machine for wire drawing, control the wire drawing temperature at 360 °C, the speed of the wire drawing machine at 3 m / min, and the deformation amount at 43% to prepare a wire material with a specification of Φ6.6 mm;

[0048] Step 5: Use a slider straightening machine for straightening, and the straightening speed is 1.4 m / s;

[0049] Step 6: Anneal the straightened wire material. Select a box-type resistance furnace for annealing, with an annealing temperature of 480 °C and a holding time of 4 hours;

[0050] Step 7: Centerless grind the wire material with a centerless grinding amount of 0.02 mm each time, and polish the surface of the wire material to prepare a finished wire material with a specification of Φ6.0 mm.

[0051] Table 2 shows the mechanical property test results of the Φ6.0 mm specification Ti-Zr alloy wire material prepared in Example 2

[0052] Sample number Rm / MPa <![CDATA[Rp 0.2 / MPa]]> A / ％ Specimen 1 1050 887 13.5 Specimen 2 1040 863 12.0

[0053] Example 3

[0054] In this example, the preparation method of the Ti-Zr alloy wire is as follows:

[0055] Step 1: Use sponge titanium, sponge zirconium, and compound TiO2 with a particle size of 3 - 12.7 mm, proportion the materials according to the alloy composition, and perform vacuum consumable melting three times to obtain a Ti-Zr alloy ingot with stable and uniform composition;

[0056] The chemical composition and mass percentage of the Ti-Zr alloy ingot are: Zr is 16.3%, Fe is 0.06%, C is 0.04%, H is 0.007%, O is 0.3%, N is 0.02%, and the balance is Ti.

[0057] Step 2: Use a quick forging machine to perform cogging forging at 1030°C for 5 hours, and use a precision forging machine to perform forging at 820°C for 4 hours. Control the deformation per heat to be 70% during forging;

[0058] Step 3: Use a tandem rolling mill for rolling. Control the rolling temperature to be 800°C, hold for 1 hour, and control the deformation per pass to be 6%;

[0059] Step 4: Use a disk wire drawing machine for drawing. Control the drawing temperature to be 300°C, the speed of the wire drawing machine to be 5 m / min, and the deformation to be controlled at 40% to prepare a wire with a Φ5.6 mm specification;

[0060] Step 5: Use a slider straightening machine for straightening, and the straightening speed is 1.8 m / s;

[0061] Step 6: Anneal the straightened wire. Select a box-type resistance furnace for annealing. The annealing temperature is 420°C, and the holding time is 4 hours;

[0062] Step 7: Perform centerless grinding on the wire. The amount of centerless grinding each time is 0.04 mm, and polish the surface of the wire to prepare a finished wire with a Φ5.0 mm specification.

[0063] Table 3 shows the mechanical property test results of the Φ5.0 mm specification Ti-Zr alloy wire prepared in Example 3

[0064] Sample number Rm / MPa <![CDATA[Rp 0.2 / MPa]]> A / ％ Specimen 1 1106 871 12.0 Specimen 2 1124 913 13.5

[0065] The test results of the examples show that due to the adoption of a matched temperature-controlled drawing (drawing temperature 300°C to 380°C, wire drawing machine speed 3 to 5 m / min, deformation amount 40% to 43%), straightening (straightening speed 1.2 m / s to 1.8 m / s) and heat treatment process (annealing temperature 420°C to 520°C), the optimized process plan of the examples can obtain wire materials with Rm 1022 to 1124 MPa, Rp 0.2 829 to 913 MPa, and A 12.0 to 17.0%. Therefore, high-strength titanium-zirconium alloy wire materials for dental products can be produced by the present invention, providing qualified raw materials for dental implant products.

[0066] The above are only the preferred embodiments of the present invention and do not impose any limitations on the present invention. Any simple modifications, changes and equivalent variations made to the above embodiments according to the technical essence of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A method for preparing a high-strength titanium-zirconium alloy wire, characterized in that: The chemical composition and mass percentage of the Ti-Zr alloy are: Zr is 13.5% to 16.5%, Fe≤0.10%, C≤0.10%, H≤0.015%, O≤0.6%, N≤0.05%, and the balance is Ti; The method for preparing the high-strength titanium-zirconium alloy wire comprises the following steps: Step 1: Prepare Ti-Zr alloy ingot by vacuum consumable three-time smelting; Step 2: Forging with a fast forging machine and a precision forging machine; Step 3, rolling by a horizontal rolling mill; Step 4: Use a disc wire drawing machine for drawing; Step 5: Use a slider straightening machine for straightening; Step 6: annealing the straightened wire; Step 7: Centerlessly grind the wire material to produce finished wire material.

2. The method for preparing a high-strength titanium-zirconium alloy wire according to claim 1, characterized in that: In step 1, titanium sponge, zirconium sponge and compound TiO2 with a particle size of 3 to 12.7 mm are used, the materials are prepared according to the alloy components, and vacuum self-consumable three-time smelting is performed to obtain a Ti-Zr alloy ingot.

3. The method for preparing the high-strength titanium-zirconium alloy wire according to claim 1, characterized in that: In step 2, the blank is forged at 950°C to 1050°C for 3 to 6 hours, and the finish forging is performed at 750°C to 850°C for 1.5 to 4.5 hours. During forging, the deformation amount of each fire is controlled at 40% to 80%.

4. The method for preparing a high-strength titanium-zirconium alloy wire according to claim 1, characterized in that: In step three, the rolling temperature is controlled at 750-820° C., kept at this temperature for 1-2 hours, and the deformation of each pass is controlled within 15%.

5. The method for preparing a high-strength titanium-zirconium alloy wire according to claim 1, characterized in that: In step 4, the drawing temperature is controlled to be 200-400° C., the wire drawing machine speed is 3-5 m / min, and the deformation amount is 30-50%.

6. The method for preparing a high-strength titanium-zirconium alloy wire according to claim 1, characterized in that: In step five, the straightening speed is 1 to 2 m / s.

7. The method for preparing a high-strength titanium-zirconium alloy wire according to claim 1, characterized in that: In step six, a box-type resistance furnace is used for annealing, the annealing temperature is 400-600° C., and the insulation time is 3-6 hours.

8. The method for preparing a high-strength titanium-zirconium alloy wire according to claim 1, characterized in that: In step seven, the centerless grinding amount is less than 0.05 mm each time, and the surface of the finished product is polished.