Titanium alloy material with ice crystal morphology and preparation method and application thereof

Abstract

The invention provides a titanium alloy material with ice crystal morphology and a preparation method and application thereof.The preparation method comprises the steps that a titanium alloy blank is subjected to at least two times of cyclic heat treatment, and one time of cyclic heat treatment sequentially comprises the heating heat treatment process and the cooling heat treatment process; after the cyclic heat treatment is finished, the titanium alloy blank is subjected to acid pickling development; and the titanium alloy blank subjected to acid pickling development serves as an anode for anodic oxidation, and the titanium alloy material with the ice crystal morphology is obtained. According to the preparation method provided by the invention, the oxidation film layers with different color ice crystal effects are formed on the surface of the titanium alloy through the combination of the circulating heat treatment and the anodic oxidation process, meanwhile, the oxidation film layers have good strength and corrosion resistance, and meanwhile, the requirements of the titanium alloy material for the performance and the appearance effect are met.

Description

Technical Field

[0001] The present invention belongs to the technical field of metal materials and relates to a titanium alloy material, in particular to a titanium alloy material with ice crystal morphology and a preparation method and application thereof. Background Art

[0002] Titanium alloys, due to their exceptional performance, have been widely used in various high-end consumer electronics products in recent years. Due to their lightweight, high-strength, and corrosion-resistant properties, titanium alloys have become a key structural and exterior component material in electronic products such as smartphones and computers. In the high-end consumer electronics sector, in particular, as consumers' expectations for products continue to rise, appearance, texture, and performance are becoming increasingly important factors in purchasing decisions.

[0003] Titanium alloys possess excellent mechanical properties and corrosion resistance. Compared to aluminum alloys and stainless steel, titanium alloys offer higher specific strength and are lighter in weight. Their corrosion resistance is particularly advantageous in electronic products, offering resistance to air, moisture, and certain chemicals, making them suitable for use in a variety of challenging environments. For high-end smartphones and other electronic devices, the use of titanium alloys can enhance their durability and extend their lifespan.

[0004] However, as consumer spending rises, they demand higher performance and aesthetics from electronic products. Titanium alloys typically have a relatively monotonous appearance, with common colors like silver-gray and gray-black presenting certain design limitations. Existing processes for treating titanium alloy surfaces include anodizing, plating, and spraying, but these different surface treatments can affect the metal's properties.

[0005] Therefore, developing new surface treatment processes to further enrich the appearance of titanium alloys and improve their performance has become an important topic in the current research and development of titanium alloy applications. Summary of the Invention

[0006] The object of the present invention is to provide a titanium alloy material with ice crystal morphology to obtain a titanium alloy workpiece with good appearance and excellent film performance.

[0007] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides a method for preparing a titanium alloy material having an ice crystal morphology, the preparation method comprising the following steps:

[0009] (1) subjecting the titanium alloy blank to at least two cyclic heat treatments, wherein one cyclic heat treatment comprises a heating process and a cooling process in sequence;

[0010] (2) After the cyclic heat treatment is completed, the titanium alloy blank is pickled and developed;

[0011] (3) The titanium alloy blank after pickling and development is used as an anode for anodization to obtain the titanium alloy material with ice crystal morphology.

[0012] The preparation method provided by the present invention forms large-sized unit cells in the titanium alloy through a cyclic heat treatment process, thereby presenting an ice crystal effect. During the temperature-raising heat treatment process, the β-phase grains in the titanium alloy are aggregated and grown, promoting the reconstruction of the surface grain boundaries. Then, during the temperature-lowering heat treatment process, the material stress is eliminated, the crystal structure of the ice crystals is solidified, and the crystal phase is stabilized, thereby obtaining an ice crystal morphology. By setting the number of cycles of the cyclic heat treatment process, the growth of the ice crystals is controlled, and the ice crystal size can be regulated between 5 and 50 mm. The surface is then treated by a pickling process to develop the ice crystals. Then, combined with the anodizing process, an oxide film layer presenting an ice crystal effect of different colors is formed on the surface of the titanium alloy, and even a two-color combination in the film layer can be achieved. At the same time, the oxide film layer has good strength and corrosion resistance, while meeting the performance and appearance requirements of the titanium alloy material.

[0013] Preferably, the number of cyclic heat treatments is ≥ 2 times, for example, it can be 2 times, 3 times, 4 times, 5 times, 6 times, 7 times or 8 times, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0014] Preferably, the heating heat treatment process in step (1) includes heating the titanium alloy billet to a first temperature and keeping it warm, and the cooling heat treatment process includes cooling the titanium alloy billet to a second temperature and keeping it warm.

[0015] Preferably, the first temperature is 1090-1110°C, for example, it can be 1090°C, 1092°C, 1095°C, 1098°C, 1100°C, 1102°C, 1105°C, 1108°C or 1110°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0016] Preferably, the holding time at the first temperature is 115-125 min, for example, 115 min, 118 min, 120 min, 122 min or 125 min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0017] Preferably, the heating rate of the first temperature is 10-20°C / min, for example, it can be 10°C / min, 12°C / min, 15°C / min, 18°C / min or 20°C / min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0018] Preferably, the second temperature is 540-560°C, for example, it can be 540°C, 542°C, 545°C, 548°C, 550°C, 552°C, 555°C, 558°C or 560°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0019] Preferably, the holding time at the second temperature is 85-95 min, for example, 85 min, 88 min, 90 min, 92 min or 95 min, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0020] Preferably, the cooling rate of the second temperature is 20-40°C / min, for example, it can be 20°C / min, 22°C / min, 25°C / min, 28°C / min, 30°C / min, 32°C / min, 35°C / min, 38°C / min or 40°C / min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0021] Preferably, the temperature-raising heat treatment process is carried out under vacuum.

[0022] Preferably, the vacuum degree of the vacuum is (1-3)×10 -3 Pa, for example, can be 1×10 -3 Pa, 1.5×10 -3 Pa, 2×10 -3 Pa, 2.5×10 -3 Pa or 3×10 -3 Pa, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0023] Preferably, the temperature-lowering heat treatment process is carried out under an inert gas atmosphere.

[0024] Preferably, the pickling solution for pickling and developing comprises hydrofluoric acid and / or nitric acid.

[0025] Preferably, the mass concentration of hydrofluoric acid in the pickling solution is 2%-5%, for example, it can be 2%, 2.5%, 3%, 3.5%, 4%, 4.5% or 5%, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0026] Preferably, the mass concentration of nitric acid in the pickling solution is 1%-2%, for example, 1%, 1.2%, 1.5%, 1.8% or 2%, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0027] Preferably, the pickling time of the pickling development is 1-2 minutes, for example, 1 minute, 1.2 minutes, 1.5 minutes, 1.8 minutes or 2 minutes, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0028] Preferably, the anodizing electrolyte comprises sodium silicate and / or sodium hydroxide.

[0029] Preferably, the concentration of sodium silicate and / or sodium hydroxide in the electrolyte is 5-10 g / L, for example, it can be 5 g / L, 6 g / L, 7 g / L, 8 g / L, 9 g / L or 10 g / L, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0030] Preferably, the anodic oxidation adopts a band voltage, and the band voltage includes at least two voltage boosting and voltage stabilization processes, and one of the voltage boosting and voltage stabilization processes includes boosting the voltage to the oxidation voltage and then stabilizing the voltage.

[0031] Preferably, the oxidation voltage is 5-150V, for example, it can be 5V, 10V, 20V, 30V, 40V, 50V, 60V, 70V, 80V, 90V, 100V, 110V, 120V, 130V, 140V or 150V, but is not limited to the listed values. Other values ​​not listed within the numerical range are also applicable, preferably 50-80V.

[0032] Under the preferred range of oxidation voltage, a two-color ice crystal morphology can be achieved.

[0033] Preferably, the boost time is 0.5-2 min, for example, 0.5 min, 0.8 min, 1 min, 1.2 min, 1.5 min, 1.8 min or 2 min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0034] Preferably, the voltage stabilization time is 0.5-2 min, for example, it can be 0.5 min, 0.8 min, 1 min, 1.2 min, 1.5 min, 1.8 min or 2 min, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0035] Preferably, the preparation method further comprises: performing pretreatment before the cyclic heat treatment in step (1).

[0036] Preferably, the pretreatment includes degreasing and oil removal and pickling in sequence.

[0037] Preferably, at least one of machining, grinding, polishing or sandblasting is performed before the pickling and development in step (2).

[0038] Preferably, the preparation method further comprises: after the anodizing in step (3), performing hydrophobic and anti-fingerprint treatment on the titanium alloy blank.

[0039] In a second aspect, the present invention provides a titanium alloy material having an ice crystal morphology, wherein the titanium alloy material is prepared by the preparation method described in the first aspect.

[0040] Preferably, the size of the ice crystals is 5-50 mm, for example, 5 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm or 50 mm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0041] In a third aspect, the present invention provides an application of the titanium alloy material with ice crystal morphology described in the first aspect, wherein the titanium alloy material is used for an appearance workpiece of an electronic device.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] The preparation method provided by the present invention combines cyclic heat treatment and anodizing process to form an oxide film layer on the surface of the titanium alloy that presents an ice crystal effect of different colors. At the same time, the oxide film layer has good strength and corrosion resistance, and meets the performance and appearance requirements of the titanium alloy material. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 is a surface morphology image of the titanium alloy material prepared in Example 1;

[0045] Figure 2 is a surface morphology image of the titanium alloy material prepared in Example 4;

[0046] Figure 3 is a surface morphology image of the titanium alloy material prepared in Example 5;

[0047] Figure 4 This is a surface morphology diagram of the titanium alloy material prepared in Example 7. DETAILED DESCRIPTION

[0048] The technical solution of the present invention is further described below by way of specific embodiments. It should be understood by those skilled in the art that the embodiments are merely to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0049] In order to clearly illustrate the technical solution of the present invention, in a specific embodiment, the titanium alloy workpiece to be processed uses a TC4 titanium plate with a size of 100×50×3 mm.

[0050] In order to clearly illustrate the technical solution of the present invention, in the specific implementation, the film strength performance test of the prepared titanium alloy material was carried out respectively. The test is as follows:

[0051] ① Salt spray test: At 35°C, the titanium alloy material is continuously sprayed with a 5% NaCl solution at a spray volume of 1.5±0.5mL / h for 72 hours. After spraying, the tape tear test is performed 5 times.

[0052] ② Thermal shock test: The titanium alloy material was placed in a thermal shock test box, first at -40°C for 30 minutes, then at 85°C for 30 minutes, which was a thermal shock cycle. A total of 72 thermal shock cycles were performed. After the cycle, it was placed at room temperature (25°C) for 4 hours and subjected to 5 tape tear tests.

[0053] ③ Chlorine water test: Immerse the titanium alloy material in a sodium hypochlorite solution with an active chlorine concentration of 2.5±0.15ppm for 72 hours, replace the sodium hypochlorite solution every 24 hours, and then perform the tape tear test 5 times.

[0054] ④ Artificial sweat test: The titanium alloy material was immersed in artificial sweat with a pH of 2.6 for 30 seconds, then directly sealed with a double-layer plastic film, placed at 80°C for 24 hours, and then subjected to 5 tape tearing tests.

[0055] ⑤ Friction resistance test: The titanium alloy material was subjected to a friction test using a wear resistance testing machine with a load of 175g weight and 150 cycles.

[0056] Example 1

[0057] This embodiment provides a method for preparing a titanium alloy material having an ice crystal morphology, the method comprising the following steps:

[0058] (1) Immerse the titanium alloy workpiece in a 50 g / L KY-418 degreasing agent solution at 60°C for 3 min to remove ash and oil. Rinse with pure water after degreasing. Then, place it in a 2% hydrofluoric acid solution for 2 min to remove the surface oxide film. Rinse with pure water and dry.

[0059] (2) The titanium alloy workpiece is placed in a heat treatment vacuum furnace for cyclic heat treatment. The process of one cyclic heat treatment includes: adjusting the vacuum degree in the furnace to 2×10 -3 Pa, the furnace temperature was raised to 1100°C at a heating rate of 15°C / min, and kept at that temperature for 120 minutes. After that, argon was introduced and the temperature was lowered to 550°C at a cooling rate of 30°C / min, and kept at that temperature for 90 minutes to complete one cycle heat treatment. The cycle heat treatment was performed four times. After the cycle heat treatment was completed, the titanium alloy workpiece was cooled to 200°C, taken out, and cooled to room temperature;

[0060] (3) The titanium alloy workpiece was pickled in a 2% hydrofluoric acid solution for 2 min to develop ice crystals, and then rinsed with pure water;

[0061] (4) The titanium alloy workpiece after development is placed in an electrolytic cell, with the titanium alloy workpiece as the anode, the graphite plate as the cathode, and the electrolyte being a NaOH solution with a concentration of 5 g / L. A DC voltage is applied for anodic oxidation. The voltage control process of anodic oxidation includes: increasing the voltage from 0 V to 30 V in 1 minute and holding the voltage for 1 minute, decreasing the voltage from 30 V to 0 V in 30 seconds, and then increasing the voltage from 0 V to 30 V in 1 minute and holding the voltage for 1 minute. The power supply is terminated, and the titanium alloy workpiece is taken out and washed with water.

[0062] (5) Place the titanium alloy workpiece in a 5 mL / L E110 sealing solution and seal it at 95 °C for 5 min. After sealing, take it out and wash it with water;

[0063] (6) The titanium alloy workpiece was placed in a sealing and lubricating agent solution with a mass concentration of 20% for 3 minutes to complete the hydrophobic and anti-fingerprint treatment. After being taken out, it was washed with water and placed in an 80°C oven for drying for 20 minutes to obtain the titanium alloy material with ice crystal morphology.

[0064] In this embodiment, the titanium alloy material prepared is as follows Figure 1 As shown, the surface presents the morphology of ice crystals, the average size of the ice crystals is 21 mm, the distribution range of the ice crystal size is 19-22 mm, the grain size is uniform and concentrated, the ice crystal color is light blue, the texture is clear, the surface has a layered feel, and the color is rich and full.

[0065] In this embodiment, the salt spray test, thermal shock test, chlorine water test, artificial sweat test and friction resistance test of the oxide film layer of the obtained titanium alloy material all showed that the surface was free of corrosion and discoloration, and the film layer did not peel off, and the film layer strength met the use requirements.

[0066] Example 2

[0067] This embodiment provides a method for preparing a titanium alloy material having an ice crystal morphology, the method comprising the following steps:

[0068] (1) Immerse the titanium alloy workpiece in a 50 g / L KY-418 degreasing agent solution at 60°C for 3 min to remove ash and oil. Rinse with pure water after degreasing. Then, place it in a 2% hydrofluoric acid solution for 2 min to remove the surface oxide film. Rinse with pure water and dry.

[0069] (2) The titanium alloy workpiece is placed in a heat treatment vacuum furnace for cyclic heat treatment. The process of one cyclic heat treatment includes: adjusting the vacuum degree in the furnace to 1×10 -3Pa, the furnace temperature was raised to 1090°C at a heating rate of 10°C / min, and kept at that temperature for 125 minutes. After that, argon gas was introduced and the temperature was lowered to 560°C at a cooling rate of 20°C / min, and kept at that temperature for 85 minutes to complete one cycle heat treatment. The cycle heat treatment was performed four times. After the cycle heat treatment was completed, the titanium alloy workpiece was cooled to 200°C, taken out, and cooled to room temperature;

[0070] (3) The titanium alloy workpiece was pickled in a 3% hydrofluoric acid solution for 1.5 min to develop ice crystals, and then rinsed with pure water;

[0071] (4) The titanium alloy workpiece after development is placed in an electrolytic cell, with the titanium alloy workpiece as the anode, the graphite plate as the cathode, and the electrolyte being a NaOH solution with a concentration of 8 g / L. A DC voltage is applied for anodic oxidation. The voltage control process of anodic oxidation includes: increasing the voltage from 0 V to 5 V in 0.5 min and holding the voltage for 2 min, decreasing the voltage from 5 V to 0 V in 30 s, and then increasing the voltage from 0 V to 5 V in 0.5 min and holding the voltage for 2 min. The power supply is terminated, and the titanium alloy workpiece is taken out and washed with water;

[0072] (5) Place the titanium alloy workpiece in a 5 mL / L E110 sealing solution and seal it at 95 °C for 5 min. After sealing, take it out and wash it with water;

[0073] (6) The titanium alloy workpiece was placed in a sealing and lubricating agent solution with a mass concentration of 20% for 3 minutes to complete the hydrophobic and anti-fingerprint treatment. After being taken out, it was washed with water and placed in an 80°C oven for drying for 20 minutes to obtain the titanium alloy material with ice crystal morphology.

[0074] In this embodiment, the surface of the prepared titanium alloy material presents an ice crystal morphology, the average size of the ice crystals is 20 mm, the ice crystal size distribution range is 18-22 mm, the grain size is uniform and concentrated, the ice crystal color is light yellow, the texture is clear, the surface has a layered feel, and the color is rich and full.

[0075] In this embodiment, the salt spray test, thermal shock test, chlorine water test, artificial sweat test and friction resistance test of the oxide film layer of the obtained titanium alloy material all showed that the surface was free of corrosion and discoloration, and the film layer did not peel off, and the film layer strength met the use requirements.

[0076] Example 3

[0077] This embodiment provides a method for preparing a titanium alloy material having an ice crystal morphology, the method comprising the following steps:

[0078] (1) Immerse the titanium alloy workpiece in a 50 g / L KY-418 degreasing agent solution at 60°C for 3 min to remove ash and oil. Rinse with pure water after degreasing. Then, place it in a 2% hydrofluoric acid solution for 2 min to remove the surface oxide film. Rinse with pure water and dry.

[0079] (2) The titanium alloy workpiece is placed in a heat treatment vacuum furnace for cyclic heat treatment. The process of one cyclic heat treatment includes: adjusting the vacuum degree in the furnace to 3×10 -3 Pa, the furnace temperature was raised to 1110°C at a heating rate of 20°C / min, and kept at that temperature for 115 minutes. After that, argon gas was introduced and the temperature was lowered to 540°C at a cooling rate of 40°C / min, and kept at that temperature for 95 minutes to complete one cycle heat treatment. The cycle heat treatment was performed four times. After the cycle heat treatment was completed, the titanium alloy workpiece was cooled to 200°C, taken out, and cooled to room temperature;

[0080] (3) The titanium alloy workpiece was pickled in a 5% hydrofluoric acid solution for 1 min to develop ice crystals, and then rinsed with pure water;

[0081] (4) The developed titanium alloy workpiece is placed in an electrolytic cell, with the titanium alloy workpiece as the anode, the graphite plate as the cathode, and the electrolyte being a NaOH solution with a concentration of 10 g / L. A DC voltage is applied for anodic oxidation. The voltage control process of anodic oxidation includes: increasing the voltage from 0 V to 150 V in 2 minutes and holding the voltage for 0.5 minutes, decreasing the voltage from 150 V to 0 V in 30 seconds, and then increasing the voltage from 0 V to 150 V in 2 minutes and holding the voltage for 0.5 minutes. The power supply is terminated, and the titanium alloy workpiece is taken out and washed with water.

[0082] (5) Place the titanium alloy workpiece in a 5 mL / L E110 sealing solution and seal it at 95 °C for 5 min. After sealing, take it out and wash it with water;

[0083] (6) The titanium alloy workpiece was placed in a sealing and lubricating agent solution with a mass concentration of 20% for 3 minutes to complete the hydrophobic and anti-fingerprint treatment. After being taken out, it was washed with water and placed in an 80°C oven for drying for 20 minutes to obtain the titanium alloy material with ice crystal morphology.

[0084] In this embodiment, the surface of the prepared titanium alloy material presents an ice crystal morphology, the average size of the ice crystals is 21 mm, the ice crystal size distribution range is 18-23 mm, the grain size is uniform and concentrated, the ice crystal color is pink-green, the texture is clear, the surface has a layered feel, and the color is rich and full.

[0085] In this embodiment, the salt spray test, thermal shock test, chlorine water test, artificial sweat test and friction resistance test of the oxide film layer of the obtained titanium alloy material all showed that the surface was free of corrosion and discoloration, and the film layer did not peel off, and the film layer strength met the use requirements.

[0086] Example 4

[0087] This embodiment provides a method for preparing a titanium alloy material with an ice crystal morphology. Compared with Example 1, the number of cyclic heat treatments in step (2) is set to 2 times, and the rest is the same as Example 1.

[0088] In this embodiment, the titanium alloy material prepared is as follows Figure 2 As shown, the surface presents the morphology of ice crystals, the average size of the ice crystals is 5mm, the distribution range of the ice crystal size is 4-6mm, the grain size is uniform and concentrated, the ice crystal color is light blue, the texture is clear, the surface has a layered feel, and the color is rich and full.

[0089] In this embodiment, the salt spray test, thermal shock test, chlorine water test, artificial sweat test and friction resistance test of the oxide film layer of the obtained titanium alloy material all showed that the surface was free of corrosion and discoloration, and the film layer did not peel off, and the film layer strength met the use requirements.

[0090] Example 5

[0091] This embodiment provides a method for preparing a titanium alloy material with an ice crystal morphology. Compared with Example 1, the oxidation voltage of the anodizing process is set from 30 V to 60 V in step (4), and the rest is the same as Example 1.

[0092] In this embodiment, the titanium alloy material prepared is as follows Figure 3 As shown, the surface presents the morphology of ice crystals, the average size of the ice crystals is 21mm, the distribution range of the ice crystal size is 19-22mm, the grain size is uniform and concentrated, the color of the ice crystals is purple and gold, the texture is clear, the surface has a layered feel, and the color is rich and full.

[0093] In this embodiment, the salt spray test, thermal shock test, chlorine water test, artificial sweat test and friction resistance test of the oxide film layer of the obtained titanium alloy material all showed that the surface was free of corrosion and discoloration, and the film layer did not peel off, and the film layer strength met the use requirements.

[0094] Example 6

[0095] This embodiment provides a method for preparing a titanium alloy material with an ice crystal morphology. Compared with Example 1, the oxidation voltage of the anodizing process is set from 30 V to 80 V in step (4), and the rest is the same as Example 1.

[0096] In this embodiment, the surface of the prepared titanium alloy material presents an ice crystal morphology, the average size of the ice crystals is 21 mm, the distribution range of the ice crystal size is 19-22 mm, the grain size is uniform and concentrated, the ice crystal color is rose red and green, the texture is clear, the surface has a layered feel, and the color is rich and full.

[0097] In this embodiment, the salt spray test, thermal shock test, chlorine water test, artificial sweat test and friction resistance test of the oxide film layer of the obtained titanium alloy material all showed that the surface was free of corrosion and discoloration, and the film layer did not peel off, and the film layer strength met the use requirements.

[0098] Example 7

[0099] This embodiment provides a method for preparing a titanium alloy material with an ice crystal morphology. Compared with Example 1, in step (4), the oxidation voltage of the anodizing is set from 30 V to 90 V, and the electrolyte is replaced by a sodium silicate solution with an equal concentration of NaOH solution. The rest is the same as Example 1.

[0100] In this embodiment, the titanium alloy material prepared is as follows Figure 4 As shown, the surface presents the morphology of ice crystals, the average size of the ice crystals is 21 mm, the distribution range of the ice crystal size is 19-22 mm, the grain size is uniform and concentrated, the ice crystals are turquoise in color, the texture is clear, the surface has a layered feel, and the color is rich and full.

[0101] In this embodiment, the salt spray test, thermal shock test, chlorine water test, artificial sweat test and friction resistance test of the oxide film layer of the obtained titanium alloy material all showed that the surface was free of corrosion and discoloration, and the film layer did not peel off, and the film layer strength met the use requirements.

[0102] Example 8

[0103] This embodiment provides a method for preparing a titanium alloy material with an ice crystal morphology. Compared with Example 1, the voltage of the anodizing in step (4) is always stabilized at 30V, and the rest is the same as Example 1.

[0104] In this embodiment, the surface of the prepared titanium alloy material presents an ice crystal morphology, the average size of the ice crystals is 21 mm, the distribution range of the ice crystal size is 19-22 mm, the grain size is uniform and concentrated, and the color of the ice crystals is bluish-gray, which is relatively dark and not full.

[0105] In this embodiment, the salt spray test, thermal shock test, chlorine water test, artificial sweat test and friction resistance test of the oxide film layer of the obtained titanium alloy material all show that the surface is free of corrosion and discoloration, and the film layer does not peel off, and the film layer strength meets the use requirements.

[0106] Comparative Example 1

[0107] This comparative example provides a method for preparing a titanium alloy material. Compared with Example 1, the pickling and development in step (2) is not performed, that is, the titanium alloy workpiece in step (2) is directly used in step (4), and the rest is the same as Example 1.

[0108] In this comparative example, the prepared titanium alloy material has no ice crystal pattern on its surface and is light blue in color.

[0109] Comparative Example 2

[0110] This comparative example provides a method for preparing a titanium alloy material. Compared with Example 1, the anodic oxidation in step (3) is not performed, and the rest is the same as Example 1.

[0111] In this comparative example, the surface of the prepared titanium alloy material presents an ice crystal morphology, the average size of the ice crystals is 20 mm, the distribution range of the ice crystal size is 18-22 mm, and the color is the original color of the metal, and cannot present the color of ice crystals.

[0112] In summary, the preparation method provided by the present invention combines cyclic heat treatment and anodizing process to form an oxide film layer on the surface of the titanium alloy that presents an ice crystal effect of different colors. At the same time, the oxide film layer has good strength and corrosion resistance, and meets the performance and appearance requirements of the titanium alloy material.

[0113] The applicant declares that the above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention fall within the scope of protection and disclosure of the present invention.

Claims

1. A method for preparing a titanium alloy material having an ice crystal morphology, characterized in that: The preparation method comprises the following steps: (1) subjecting the titanium alloy blank to at least two cyclic heat treatments, wherein one cyclic heat treatment comprises a heating process and a cooling process in sequence; (2) After the cyclic heat treatment is completed, the titanium alloy blank is pickled and developed; (3) The titanium alloy blank after pickling and development is used as an anode for anodization to obtain the titanium alloy material with ice crystal morphology.

2. The preparation method according to claim 1, characterized in that The heating heat treatment process in step (1) comprises heating the titanium alloy blank to a first temperature and keeping the temperature constant, and the cooling heat treatment process comprises cooling the titanium alloy blank to a second temperature and keeping the temperature constant; Preferably, the first temperature is 1090-1110°C; Preferably, the holding time at the first temperature is 115-125 min; Preferably, the heating rate of the first temperature is 10-20°C / min; Preferably, the second temperature is 540-560°C; Preferably, the holding time at the second temperature is 85-95 minutes; Preferably, the cooling rate of the second temperature is 20-40°C / min.

3. The preparation method according to claim 1 or 2, characterized in that The temperature-raising heat treatment process is carried out under vacuum; Preferably, the vacuum degree of the vacuum is (1-3)×10 -3 Pa; Preferably, the temperature-lowering heat treatment process is carried out under an inert gas atmosphere.

4. The preparation method according to any one of claims 1 to 3, characterized in that The pickling solution for pickling and developing includes hydrofluoric acid and / or nitric acid; Preferably, the mass concentration of hydrofluoric acid in the pickling solution is 2%-5%; Preferably, the mass concentration of nitric acid in the pickling solution is 1%-2%.

5. The preparation method according to any one of claims 1 to 4, characterized in that The pickling time of the pickling development is 1-2 minutes.

6. The preparation method according to any one of claims 1 to 5, characterized in that The electrolyte for the anodization comprises sodium silicate and / or sodium hydroxide; Preferably, the concentration of sodium silicate and / or sodium hydroxide in the electrolyte is 5-10 g / L.

7. The preparation method according to any one of claims 1 to 6, characterized in that The anodic oxidation adopts a band voltage, and the band voltage includes at least two voltage boosting and voltage stabilization processes, and one of the voltage boosting and voltage stabilization processes includes boosting the voltage to the oxidation voltage and then stabilizing the voltage.

8. The preparation method according to claim 7, characterized in that The oxidation voltage is 5-150V; Preferably, the boosting time is 0.5-2 min; Preferably, the voltage stabilization time is 0.5-2 minutes.

9. A titanium alloy material with ice crystal morphology, characterized in that: The titanium alloy material is prepared by the preparation method according to any one of claims 1 to 8; The size of the ice crystals is 5-50 mm.

10. An application of the titanium alloy material with ice crystal morphology according to claim 9, characterized in that: The titanium alloy material is used for the appearance workpiece of electronic equipment.

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