A rolling method for obtaining ultra-high strength low oxygen titanium-zirconium alloy

Abstract

The application discloses a rolling method for obtaining super-high-strength low-oxygen titanium-zirconium alloy. The method comprises the following steps: smelting low-oxygen titanium-zirconium alloy; subjecting the alloy to solid solution treatment and water quenching; pickling the alloy to remove surface oxide scales, and cleaning and drying the alloy; warm rolling the alloy; warm rolling the alloy at a lower temperature, or liquid nitrogen cold rolling the alloy after recrystallization annealing and supplementing with stress relief annealing; cleaning and drying the alloy; annealing the alloy; and cleaning and drying the alloy. The process provided by the application is simple and easy to implement, and the devices and reagents involved are common and easy to obtain. The low-oxygen titanium-zirconium alloy obtained by using the process provided by the application has excellent strength, and meets the material requirements of clinical application of dental implant bodies.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of metal material processing technology, and particularly relates to a rolling method for obtaining super-high-strength low-oxygen titanium-zirconium alloy. BACKGROUND

[0002] Titanium-zirconium alloy is a good new implant material, which has a wide application prospect in the field of dental implantation due to the fact that it makes up for the insufficient mechanical properties of pure titanium implant and the insufficient biocompatibility of Ti6Al4V implant, and has a relatively appropriate price level.

[0003] In view of the problems of insufficient strength and insufficient fatigue fracture resistance of traditional pure titanium implant, the binary titanium-zirconium alloy with 14-17wt% Zr content has become the preferred material for narrow diameter implant due to its good mechanical properties, corrosion resistance and biocompatibility. In recent years, oxygen-containing titanium alloy has become a hot spot in the field. The addition of oxygen can have a good strengthening effect on titanium alloy, but a high content of oxygen will significantly affect the alloy fracture elongation and severely inhibit the twinning deformation. In addition to composition control, process optimization is also an important way to improve the performance of the alloy. Therefore, it is of great significance to improve the comprehensive mechanical properties of titanium-zirconium alloy and meet the clinical requirements by improving the rolling process of low-oxygen titanium-zirconium alloy. SUMMARY

[0004] The application aims to provide two rolling and heat treatment process flows for obtaining super-high-strength low-oxygen titanium-zirconium alloy.

[0005] In order to achieve the above-mentioned purpose, the technical route of the application is as follows: as a first aspect, a rolling method for obtaining super-high-strength low-oxygen titanium-zirconium alloy is provided, which comprises the following steps:

[0006] The titanium-zirconium alloy with an oxygen mass percentage content of ≤0.18% is subjected to solid solution treatment at 900℃ for 0.5h and water quenching to ensure the uniformity of the structure and composition; the surface oxide scale is removed by acid pickling with an acid etching liquid, and then the titanium-zirconium alloy is cleaned with a cleaning liquid and dried;

[0007] The cleaned titanium-zirconium alloy is subjected to warm rolling at a temperature of 500℃; the titanium-zirconium alloy after warm rolling is subjected to one of the following treatments until the total reduction rate is 90%: (1) cold rolling after recrystallization annealing, (2) warm rolling at a temperature lower than 400℃;

[0008] 400℃ temperature for 1h annealing; cleaning and drying treatment with a cleaning liquid.

[0009] The application also provides two preferred schemes, one of which is as follows:

[0010] 1) Melting the low-oxygen titanium-zirconium alloy to obtain the low-oxygen titanium-zirconium alloy as a process raw material;

[0011] 2) Solution treatment and water quenching of the titanium-zirconium alloy;

[0012] 3) Pickling of the titanium-zirconium alloy with an acid pickling solution to remove the surface oxide scale, washing with a washing solution and drying;

[0013] 4) Warm rolling of the washed titanium-zirconium alloy at a temperature of 500°C until a reduction of 75% is achieved;

[0014] 5) Heat treatment of the warm-rolled titanium-zirconium alloy at a recrystallization temperature of 750°C for 1 h;

[0015] 6) Liquid nitrogen cold rolling of the recrystallized titanium-zirconium alloy, with each stage being annealed at a temperature of 400°C for 1 h until a reduction of 60% is achieved, resulting in a total reduction of 90% compared to the initial material;

[0016] wherein the alloy is completely immersed in liquid nitrogen for more than 3 min before each rolling to ensure that the alloy reaches the required temperature, and the roll gap of the rolling mill is slowly reduced, with a single rolling reduction of < 2% being maintained, with stress relief annealing being performed after each stage of 20% reduction, and unidirectional rolling being used.

[0017] 7) Washing and drying of the treated titanium-zirconium alloy with a washing solution.

[0018] and two as follows:

[0019] 1) Melting of a low-oxygen titanium-zirconium alloy as a process starting material;

[0020] 2) Solution treatment and water quenching of the titanium-zirconium alloy;

[0021] 3) Pickling of the titanium-zirconium alloy with an acid pickling solution to remove the surface oxide scale, washing with a washing solution and drying;

[0022] 4) Warm rolling of the washed titanium-zirconium alloy at a temperature of 500°C until a reduction of 66.7% is achieved;

[0023] 5) Rolling of the warm-rolled titanium-zirconium alloy at a temperature of less than 400°C, preferably 200°C, until a reduction of 70% is achieved, resulting in a total reduction of 90% compared to the initial material;

[0024] wherein the alloy is held for 5 min before each rolling to ensure that the alloy reaches the required temperature, and the roll gap of the rolling mill is slowly reduced, with a single rolling reduction of < 4% being maintained until the target reduction is achieved, and unidirectional rolling being used.

[0025] 6) the titanium-zirconium alloy after rolling is annealed at 400℃ for 1h;

[0026] 7) the titanium-zirconium alloy after processing is cleaned with a cleaning solution and dried.

[0027] In the method, the titanium-zirconium alloy after cleaning is warm-rolled at 500℃, specifically, the alloy is kept at the temperature for more than 5min before each rolling to ensure that the alloy reaches the required temperature, the roller spacing of the rolling machine is slowly reduced, the single-rolling reduction rate is kept at ≤5%, until the target reduction rate is reached, and single-direction rolling is adopted.

[0028] In the low-oxygen titanium-zirconium alloy, the mass percentage of Zr is ≥14% and ≤17%. In the method, the process of smelting is as follows: using industrial-grade titanium sponge, zirconium sponge and titanium dioxide as raw materials, a cast ingot is obtained by vacuum water-cooled copper crucible suspension furnace smelting, and the alloy block is obtained by hot forging to eliminate defects and then wire cutting.

[0029] In the method, the etching solution used for pickling is HF:HNO3:H2O = 1:3:16, the cleaning solution is an acetone solution, and the cleaning method is ultrasonic cleaning.

[0030] In the method, the annealing process is uniformly 400℃ for 1h, which aims to eliminate the residual stress generated in the alloy during rolling, and to ensure smooth rolling without fracture. In step 6) of the first aspect of the technical solution, annealing is performed every time the stage reduction rate reaches 20%, the stage reduction rate is calculated based on the alloy of the previous stage rather than the initial state of the alloy, and the total annealing is 4 times. The reduction rate of the alloy in the liquid nitrogen cold rolling process stage is 60%.

[0031] As a second aspect, the application provides a high-strength low-oxygen titanium-zirconium alloy rolled by the method, and the use of the alloy in preparing dental implant bodies.

[0032] The beneficial effects of the application are as follows:

[0033] The rolling process provided by the application for obtaining a high-strength low-oxygen titanium-zirconium alloy is simple and clear, easy to implement, and the process equipment and chemicals involved are common and easy to obtain. Using the process provided by the application can make the titanium-zirconium alloy have fine grains and make the material strong and tough, meeting the material requirements of clinical application of dental implant bodies. BRIEF DESCRIPTION OF DRAWINGS

[0034] The application will be further described below in conjunction with the drawings and examples;

[0035] Figure 1The original metallographic structure of the titanium-zirconium alloy strip material with 16% zirconium content and 0.17% oxygen content after solid solution quenching treatment is taken by a metallographic microscope.

[0036] Figure 2 The metallographic structure of the titanium-zirconium alloy strip material with 16% zirconium content and 0.17% oxygen content after the rolling process of technical solution one and the tensile test in Example 1 is taken by a metallographic microscope.

[0037] Figure 3 The metallographic structure of the titanium-zirconium alloy strip material with 16% zirconium content and 0.17% oxygen content after the rolling process of technical solution two and the tensile test in Example 2 is taken by a metallographic microscope.

[0038] Figure 4 The stress-strain curve of the titanium-zirconium alloy strip material with 16% zirconium content and 0.17% oxygen content after the rolling process of technical solution one and the tensile test in Example 1.

[0039] Figure 5 The stress-strain curve of the titanium-zirconium alloy strip material with 16% zirconium content and 0.17% oxygen content after the rolling process of technical solution two and the tensile test in Example 2. DETAILED DESCRIPTION

[0040] The embodiments, features and aspects of the present application will be described in detail below with reference to the accompanying drawings, but are not limited to the present application. Any one of the embodiments expanded based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without making creative labor, belong to the scope of protection of the present application.

[0041] Example 1

[0042] The titanium-zirconium alloy strip material used has the elemental mass percentage of Zr%=16%, O%=0.17%, and can be written as Ti-16Zr-0.17O. The instruments used in the rolling process include a KQ-50B ultrasonic cleaner, a box-type resistance furnace, a Nabertherm brick structure muffle furnace, an optical metallographic microscope, a rolling machine, and a tensile testing machine. The titanium-zirconium alloy with an initial thickness of 12 mm is placed in a furnace, and is subjected to a solid solution treatment at a temperature of 900°C for 0.5 h, and then is subjected to water quenching, so as to ensure the uniformity of the structure and composition. Subsequently, the surface oxide scale is removed by acid pickling using a corrosion solution with a volume ratio of HF:HNO3:H2O=1:3:16, and the titanium-zirconium alloy is cleaned and dried using an acetone solution. Then, the titanium-zirconium alloy with a thickness of 12 mm is rolled to a thickness of 3 mm at a temperature of 500°C, and then is placed in a furnace and is subjected to recrystallization annealing at a temperature of 750°C for 1 h. Subsequently, the titanium-zirconium alloy with a thickness of 3 mm is subjected to cold rolling in liquid nitrogen, and is subjected to stress relief annealing at a temperature of 400°C for 1 h after being rolled to a thickness of 2.4 mm, 1.9 mm, 1.5 mm, and 1.2 mm, respectively, so as to ensure the smoothness of the rolling process and to prevent the alloy from being easily rolled to breakage. The titanium-zirconium alloy after the process is subjected to a tensile test, and the stress-strain curve obtained is shown in FIG. 1. The tensile strength of the material is greater than 1110 MPa, and the elongation at break reaches about 13%, which shows excellent mechanical properties. Figure 4 The titanium-zirconium alloy after the tensile test is embedded and polished to prepare a metallographic sample, and the metallographic sample is observed using a metallographic microscope. The obtained metallographic image is shown in FIG. 2. It is found that the grains are greatly refined and part of the twinning appears. Figure 2 The titanium-zirconium alloy after the tensile test is embedded and polished to prepare a metallographic sample, and the metallographic sample is observed using a metallographic microscope. The obtained metallographic image is shown in FIG. 2. It is found that the grains are greatly refined and part of the twinning appears.

[0043] Example 2

[0044] The titanium-zirconium alloy strip material used is Ti-16Zr-0.17O. The instruments used in the rolling process are the same as those described in Example 1. The titanium-zirconium alloy with an initial thickness of 12 mm is placed in a furnace, and is subjected to a solid solution treatment at a temperature of 900°C for 0.5 h, and then is subjected to water quenching, so as to ensure the uniformity of the structure and composition. Subsequently, the surface oxide scale is removed by acid pickling using a corrosion solution with a volume ratio of HF:HNO3:H2O=1:3:16, and the titanium-zirconium alloy is cleaned and dried using an acetone solution. Then, the titanium-zirconium alloy with a thickness of 12 mm is rolled to a thickness of 4 mm at a temperature of 500°C, and then the titanium-zirconium alloy with a thickness of 4 mm is rolled to a thickness of 1.2 mm at a temperature of 200°C, and is subjected to stress relief annealing at a temperature of 400°C for 1 h. The titanium-zirconium alloy after the process is subjected to a tensile test, and the stress-strain curve obtained is shown in FIG. 3. The tensile strength of the material reaches 1030 MPa, and the elongation at break reaches about 15%, which shows excellent mechanical properties. Figure 5 The titanium-zirconium alloy after the tensile test is embedded and polished to prepare a metallographic sample, and the metallographic sample is observed using a metallographic microscope. The obtained metallographic image is shown in FIG. 4. It is found that the grains are greatly refined and part of the twinning appears. Figure 3 The titanium-zirconium alloy after the tensile test is embedded and polished to prepare a metallographic sample, and the metallographic sample is observed using a metallographic microscope. The obtained metallographic image is shown in FIG. 4. It is found that the grains are greatly refined and part of the twinning appears.

[0045] The above examples are used to explain the present application, but are not intended to limit the present application, and any modification and change made to the present application within the spirit and protection scope of the claims of the present application, all fall into the protection scope of the present application.

Claims

1. A rolling method for obtaining an ultra-high strength low-oxygen titanium-zirconium alloy, characterized by, The method comprises the following steps: The titanium-zirconium alloy with oxygen content of less than or equal to 0.18% is subjected to solid solution treatment at 900 ℃ for 0.5 h and water quenching to ensure uniformity of the structure and composition; the titanium-zirconium alloy is subjected to pickling with an acid etching solution to remove the surface oxide skin, and then is subjected to cleaning with a cleaning solution and drying; The cleaned titanium-zirconium alloy is subjected to warm rolling at 500 ℃; the titanium-zirconium alloy after warm rolling is subjected to one of the following treatments until the total reduction rate is 90%: (1) cold rolling after recrystallization annealing, (2) warm rolling at a temperature lower than 400 ℃; 1 h annealing at 400 ℃; cleaning with a cleaning solution and drying.

2. The rolling method according to claim 1, characterized in that: In the (1), the cold rolling after recrystallization annealing is specifically: the titanium-zirconium alloy after warm rolling to a reduction rate of 75% is subjected to heat treatment at a recrystallization temperature of 750 ℃ for 1 h; the titanium-zirconium alloy after recrystallization is subjected to cold rolling under the action of liquid nitrogen, during which the titanium-zirconium alloy is subjected to 1 h annealing at 400 ℃ for multiple times with intervals until the total reduction rate is 90%.

3. The rolling method according to claim 1, characterized in that: In the (2), the warm rolling at a temperature lower than 400 ℃ is specifically: the titanium-zirconium alloy after warm rolling to a reduction rate of 66.7% is subjected to rolling at a temperature lower than 400 ℃ until the total reduction rate is 90%.

4. The rolling method according to claim 1, characterized in that: The acid etching solution has a component composition by volume ratio of HF:HNO3:H2O = 1:3:16; the cleaning solution is an acetone solution, and the cleaning is performed by ultrasonic cleaning.

5. The rolling method according to claim 1, characterized in that: The warm rolling of the cleaned titanium-zirconium alloy at 500 ℃ is specifically: the titanium-zirconium alloy is kept at 500 ℃ for more than 5 min before each rolling to ensure that the titanium-zirconium alloy reaches the required temperature, and the roller spacing of the rolling mill is slowly reduced, the single rolling reduction rate is kept to be less than or equal to 5% until the target reduction rate is reached, and single direction rolling is adopted.

6. The rolling method according to claim 2, characterized in that: The cold rolling of the titanium-zirconium alloy after recrystallization under the action of liquid nitrogen, during which the titanium-zirconium alloy is subjected to 1 h annealing at 400 ℃ for multiple times with intervals until the total reduction rate is 90%, is specifically: the titanium-zirconium alloy is completely immersed in liquid nitrogen for more than 3 min before each rolling to ensure that the titanium-zirconium alloy reaches the required temperature, and the roller spacing of the rolling mill is slowly reduced, the single rolling reduction rate is kept to be less than or equal to 2%, the titanium-zirconium alloy is subjected to stress relief annealing at each stage reduction rate of 20%, and single direction rolling is adopted.

7. The rolling method according to claim 3, characterized in that: The rolling of the titanium-zirconium alloy after warm rolling to a reduction rate of 66.7% at a temperature lower than 400 ℃ until the total reduction rate is 90% is specifically: the titanium-zirconium alloy is kept at a temperature lower than 400 ℃ for 5 min before each rolling to ensure that the titanium-zirconium alloy reaches the required temperature, and the roller spacing of the rolling mill is slowly reduced, the single rolling reduction rate is kept to be less than or equal to 4% until the target reduction rate is reached, and single direction rolling is adopted.

8. The rolling method according to claim 1, characterized in that: In the low-oxygen titanium-zirconium alloy, the mass percentage content of Zr is greater than or equal to 14% and less than or equal to 17%.

9. A high-strength low-oxygen titanium-zirconium alloy obtained by the rolling method of claim 1.

10. Use of the high-strength low-oxygen titanium-zirconium alloy of claim 9 in the preparation of a dental implant body.

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