Search

CN-121976273-A - Black micro-arc oxidation ceramic film for pure titanium and preparation method and application thereof

CN121976273ACN 121976273 ACN121976273 ACN 121976273ACN-121976273-A

Abstract

The invention belongs to the technical field of metal surface treatment, and discloses a pure titanium black micro-arc oxidation ceramic film and a preparation method and application thereof. The preparation method comprises the steps of dissolving sodium silicate and potassium permanganate in water, regulating pH to 9-13 by using sodium hydroxide and hydrogen peroxide to obtain a simplified micro-arc oxidation electrolyte without other solvents, immersing a pure titanium test piece into the electrolyte by using a double-pulse power supply to apply a gradient positive voltage of 200-600V and a constant negative voltage, and washing and drying the pure titanium test piece to obtain a target film layer by matching 500-1500 Hz frequency, 20-70A/dm 2 current density and 5-50% duty ratio. The method uses potassium permanganate as a coloring agent, does not need an extra solvent, has simple and convenient pH adjustment process, can reduce energy consumption and shrinkage time by gradient voltage control, can regulate and control time of each voltage stage to match hand feeling and hardness requirements, and ensures that the prepared film has uniform chromatic aberration (delta E 00 is less than 0.5) and flat surface (the film thickness is 10-70 mu m), so that the TA1 pure titanium can obtain a matte ceramic texture film (60-degree gloss is 0.5-5 GU) and has excellent blackness (L is less than 20).

Inventors

  • WANG ZHENWEI
  • Li Taihan
  • ZHU WANTING
  • LI LIANJING

Assignees

  • 上海应用技术大学

Dates

Publication Date
20260505
Application Date
20260226

Claims (10)

  1. 1. The preparation method of the black micro-arc oxidation ceramic film for the pure titanium is characterized by comprising the following steps of: S1, dissolving sodium silicate and potassium permanganate in water, and adding sodium hydroxide and hydrogen peroxide to adjust the pH value to 9-13 to obtain a micro-arc oxidation electrolyte; And S2, immersing a pure titanium test piece serving as an anode into the micro-arc oxidation electrolyte configured in the step S1, setting gradient positive voltage and constant negative voltage by adopting a double-pulse power supply, wherein the positive voltage range is 200-600V, the frequency is 500-1500 Hz, the current density is 20-70A/dm 2 , the duty ratio is 5% -50%, the micro-arc oxidation time is 3-15 min, taking out the test piece, washing and drying the test piece, and obtaining the black micro-arc oxidation ceramic film on the surface of the test piece.
  2. 2. The method for preparing a black micro-arc oxidation ceramic film for pure titanium according to claim 1, wherein in S1, the pH is regulated by sodium hydroxide and hydrogen peroxide, the content of each component in the micro-arc oxidation electrolyte is 5-15 g/L of sodium silicate, 3-12 g/L of potassium permanganate, 0.5-2 g/L of sodium hydroxide and 1-5 g/L of hydrogen peroxide. Wherein the mass concentration ratio of potassium permanganate to sodium silicate is (0.2:1) to (0.8:1).
  3. 3. The method for preparing a black micro-arc oxidation ceramic film for pure titanium according to claim 1, wherein in S2, the specific arrangement of the gradient positive voltage and the constant negative voltage is as follows: the first stage, wherein the positive voltage regulation interval is 0-220V, the positive voltage is gradually increased from 0V to 220V on the premise of keeping the negative voltage at 200V, and the voltage interval is maintained at 1-8 min; the second stage, wherein the positive voltage regulation interval is 220-300V, the setting of negative voltage 200V is continued, the positive voltage is further increased from 220V to 300V, and 0-6 min is maintained; The third stage, wherein the positive voltage regulation interval is 300-400V, the negative voltage is kept at 200V, the positive voltage is sequentially increased from 300V to 400V, and 0-5 min is maintained; The fourth stage, wherein the positive voltage regulation interval is 400-500V, the negative voltage is kept at 200-V, the positive voltage is increased from 400V to 500-V, and 0-4 min is maintained; And in the fifth stage, the positive voltage regulation interval is 500-600V, and under the condition that the negative voltage is 200-V constant, the positive voltage is increased from 500V to 600V, and 0-3 min is maintained.
  4. 4. The method for preparing a black micro-arc oxidized ceramic film for pure titanium according to claim 1, wherein, in S2, The power frequency range is 500-1500 Hz, preferably 800 Hz, and the frequency change rate is not more than 50 Hz/s; the current density of the power supply is set to be 50-70A/dm 2 , and the negative current density is set to be 20-35A/dm 2 ; the duty ratio of the power supply is 20% -40% of positive pulse duty ratio, 5% -15% of negative pulse duty ratio and 5% -50% of total duty ratio.
  5. 5. The method for preparing a black micro-arc oxidation ceramic film for pure titanium according to claim 1, wherein in S2, the temperature of the micro-arc oxidation electrolyte is less than or equal to 30 ℃.
  6. 6. The method for preparing a black micro-arc oxidation ceramic film for pure titanium according to claim 5, wherein the micro-arc oxidation electrolyte temperature is controlled by a circulating cooling system, the flow rate of the cooling liquid in the circulating cooling system is 8-60L/min, and the temperature change per minute is controlled within +/-1 ℃.
  7. 7. A black micro-arc oxidized ceramic film, characterized in that it is produced by the method according to any one of claims 1 to 6.
  8. 8. The black micro-arc oxidized ceramic film according to claim 7, wherein the phase composition of the ceramic film comprises anatase TiO 2 , rutile TiO 2 , and manganese-titanium composite oxides formed by potassium permanganate decomposition doping, including but not limited to MnTiO 3 、Mn 2 TiO 4 or amorphous manganese titanium oxides.
  9. 9. A black micro-arc oxidized ceramic film according to any of claims 7 to 8, wherein the macroscopic effects of the black micro-arc oxidized ceramic film comprise: (1) Blackness is measured according to a CIELAB chromaticity system, wherein the chromaticity comprehensive index meets L≤20, and |a|ltoreq.1.0 and |b|ltoreq.1.0; (2) Calculating chromatic aberration, namely calculating chromatic aberration delta E 00 which is less than or equal to 1 among products in the same batch according to a CIEDE2000 chromatic aberration formula; (3) The thickness of the ceramic film is 10-70 μm, preferably 30-60 μm; (4) The microhardness of the ceramic film is not lower than 450 HV, preferably not lower than 550 HV; (5) Roughness, namely the arithmetic average roughness Ra of the ceramic film is 1-3 mu m; (6) Bonding force is tested by a cross-cut method according to the ASTM D3359 standard, and the bonding force between the ceramic film and the pure titanium matrix reaches the highest level 0; (7) Gloss is that the gloss of the ceramic film is 0.5-5 GU under 60 degree measuring angle according to GB/T9754-2007 standard; (8) The hydrophobicity is that the contact angle of the ceramic film with water is more than or equal to 100 degrees, preferably more than or equal to 110 degrees; (10) The wear resistance and environmental resistance are that the film layer has no bottom exposure and the change of glossiness is less than or equal to 10% after 1000 rounds of the RCA paper tape wear resistance test, and has no bubbling, falling or color change after 80 ℃ water boiling according to GB/T9274-1988; (11) The adhesive force and durability are tested according to the ASTM D3359 standard, the bonding force is 0 grade, and the plating layer is not fallen off or the falling area is not more than 5% according to the GB/T9286-2021 standard test; (12) Corrosion resistance, namely, the neutral salt fog 72H does not corrode; (13) The ceramic membrane components are inorganic oxides, do not contain organic dyes and heavy metal additives, and the heavy metal precipitation amount accords with the limit requirement of GB 4806.10-2016 national food safety standard metal materials and products for food contact; (14) The antibacterial performance is that the 24H antibacterial rate to escherichia coli and staphylococcus aureus is more than or equal to 99.5 percent, and the antibacterial rate after 100 times of dish washing cycle is more than or equal to 98 percent; (15) Pencil hardness, namely, no obvious scratch is qualified by using a pencil with the hardness of 3H or more; (16) Impact resistance performance after impact resistance test according to QB/T2933-2008 cup standard, the film layer has no crack, peeling or foaming.
  10. 10. The application of the black micro-arc oxidation ceramic film according to claims 7-8, which is characterized by being applied to the surface of a pure titanium product, wherein the pure titanium product is a pure titanium TA1 cup, a kitchen ware or an outdoor article.

Description

Black micro-arc oxidation ceramic film for pure titanium and preparation method and application thereof Technical Field The invention relates to the technical field of metal surface treatment, in particular to a black micro-arc oxidation ceramic film for pure titanium, and a preparation method and application thereof. Background Pure titanium (e.g., TA 1) has been increasingly used in the fields of high-end medical devices, consumer electronics, and daily appliances (e.g., titanium cups) because of its excellent light weight, corrosion resistance, and biocompatibility. Particularly in the high-end commercial titanium cup market, a deep and uniform pure black matte surface is favored due to the stable and convergent visual characteristics. However, achieving a surface treatment technology that combines excellent blackness, uniform matte texture, high binding force, excellent durability and meets the green environmental requirements on a pure titanium substrate remains a major challenge facing the current industry. At present, the black or functional surface treatment of titanium materials mainly depends on technologies such as anodic oxidation, micro-arc oxidation and the like in China. The existing micro-arc oxidation technical scheme has obvious defects in the aspects of environmental protection, health and safety and process simplification while pursuing performance: The environment and health risks of the coloring system are that the existing black micro-arc oxidation technology mostly adopts the complex coloring of heavy metal salts such as vanadium salt, copper salt and the like (such as CN 202210633567.7) or the complex coloring of ferric salt and copper salt (such as CN 202110664164.4). Vanadium salts (such as sodium vanadate) have potential biotoxicity and environmental hazard, the waste liquid treatment is complex and the cost is high, while ferric salt and cupric salt systems have relatively low toxicity, but still belong to heavy metal salts, and the use and the discharge of the vanadium salts need to be strictly controlled. More importantly, these processes often rely on organic complexing agents (e.g., EDTA) to stabilize the solution, increasing Chemical Oxygen Demand (COD) and treatment difficulties of the waste stream. In contrast, the use of environmentally friendly inorganic salts as colorants is a superior development direction. Harmful substances are introduced in the pretreatment or post-treatment process, and in order to obtain special performances such as superhydrophobicity, high binding force and the like, auxiliary processes with hidden environmental protection hazards are adopted in some technologies. For example, when preparing the super-hydrophobic film layer on the titanium alloy, electrochemical deposition is additionally carried out after micro-arc oxidation, cerium salt, long-chain organic acid and other components (such as CN 202410263662.1) are introduced, the process chain length is long, and the wastewater components are complex. More significantly, in order to strengthen the binding force of the coating, hydrofluoric acid is definitely used for pickling and activating (such as CN202511031406.0 and Hinox) in the pretreatment stage aiming at the process of the pure titanium cup, the hydrofluoric acid belongs to highly toxic chemicals, and extremely high requirements are put on the operation safety, the waste liquid treatment and the potential residual risk of the final product, which are contrary to the concept of healthy consumer products. Aiming at the problems of process complexity and suitability of pure titanium base materials, the prior art is mostly developed for titanium alloys such as TC4, and the complex multi-section electric parameters (such as a two-section constant current method of CN 202210633567.7) or complex electrolyte systems (such as CN 202511031406.0) added with various organic additives, nano particles and silane coupling agents, but the prior art aims at improving the performance, but also has the problems of narrow process window, large control difficulty, poor solution stability and high raw material cost. The complex process designed for the titanium alloy is transplanted to pure titanium with uniform components, so that the uniformity of a film layer is poor and the color difference is large possibly caused by the difference of discharge characteristics, and the disadvantages of environmental protection and economy are inherited unnecessarily. Therefore, the development of a simple and efficient coloring film forming system matched with the discharge characteristics of pure titanium has important value. The balance of the comprehensive performance and the green manufacturing of the film is difficult for the existing scheme in the market to simultaneously meet the double requirements of high performance and greenization. The method has the advantages that the production efficiency and the environmental friendliness are sacrificed by adopting a mu