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CN-121976163-A - Surface modification method based on ion implantation method

CN121976163ACN 121976163 ACN121976163 ACN 121976163ACN-121976163-A

Abstract

The invention relates to the technical field of surface modification, and discloses a surface modification method based on an ion implantation method, which comprises the following steps of carrying out surface pretreatment on a titanium-based or cobalt-chromium-based implant; the method comprises the steps of forming an interface steady-state layer by low-energy nitrogen ion implantation, forming a discontinuous anti-migration blocking layer by low-concentration oxygen ion co-implantation on the steady-state layer, sequentially performing calcium ion, zinc ion and silver ion implantation, obtaining a depth gradient structure from inside to outside through bi-phase modulation bias, then performing oxygen ion directional implantation to form a non-stoichiometric oxide layer, performing alternating electric field aging in the atmosphere of water vapor and phosphate to construct an ion capturing layer, and finally performing sterilization and sealing on a processed workpiece. The invention is beneficial to slowing down the migration and agglomeration of functional ions and improving the long-term stability of the surface of the implant by constructing a multilayer cooperative structure and a dynamic ion regulation mechanism.

Inventors

  • WEI XIAN
  • LIU XIAOFEI
  • YANG WENJIN

Assignees

  • 太原工业学院

Dates

Publication Date
20260505
Application Date
20260129

Claims (7)

  1. 1. A surface modification method based on an ion implantation method, comprising the steps of: S1) surface pretreatment, namely mechanically polishing a titanium-based or cobalt-chromium-based implant, carrying out ultrasonic cleaning and carrying out inert gas plasma decontamination treatment to obtain a substrate surface with the surface roughness Ra less than or equal to 0.25 mu m; S2) forming an interface steady-state layer, namely pre-implanting low-energy nitrogen ions to form an inner layer interface steady-state layer, wherein the low-energy nitrogen ions are implanted at the energy of 30-80 keV and the dosage of 1X 10 16 ～5×10 17 ions/cm 2 , and the thickness of the steady-state layer is 20-80 nm; s3) forming an anti-migration blocking layer, namely performing low-concentration oxygen ion co-injection on the interface steady-state layer, wherein the energy is 5-15 keV, the dosage is 1 multiplied by 10 15 ～5×10 15 ions/cm 2 , and a discontinuous anti-migration blocking layer containing Ti-O-N or Cr-O-N sites is formed to inhibit inward diffusion of outer layer ions; s4) multicomponent functional ion implantation: sequentially implanting calcium ions, zinc ions and silver ions after the step S3, and performing implantation control by adopting a bi-phase modulation bias signal, wherein the bias amplitude of the first stage is 20-50V higher than that of the second stage; wherein the implantation energy of calcium ions is 40-80 keV, the dosage is 5 x 10 16 ～2×10 17 ions/cm 2 , The zinc ion implantation energy is 25-50 keV, the dosage is 2 x 10 16 ～1×10 17 ions/cm 2 , The implantation energy of silver ions is 10-25 keV, the dosage is 1X 10 15 ～5×10 15 ions/cm 2 , The depth gradient distribution structure of the calcium, zinc and silver from inside to outside is obtained through energy setting; S5) oxygen ion directional injection, namely implementing oxygen ion directional injection after the step S4, wherein the energy is 10-40 keV, the dosage is 2 multiplied by 10 16 ～8×10 16 ions/cm 2 , and a non-stoichiometric oxide layer with the oxygen/metal ratio of 1.2-1.8 is formed; S6) dynamic ion capturing aging, namely placing the injected workpiece in a water vapor environment with the temperature of 37-60 ℃ and the relative humidity of more than or equal to 90%, introducing phosphate buffer atmosphere with the equivalent of 0.05-0.50 mol/L for 24-48 h aging, applying an alternating electric field with the frequency of 0.1-1 Hz and the potential amplitude of +/-0.5V in the aging process, so that shallow silver ions migrate to phosphate coordination sites along oxygen vacancies to form an ion capturing layer; S7) aseptic treatment, namely sterilizing the aged workpiece by damp heat or gamma irradiation and sealing.
  2. 2. The method of claim 1, wherein the substrate temperature is not higher than 200 ℃ during the implantation in step S2, and a pulse bias of 10-50 khz is applied to obtain a uniform steady-state layer.
  3. 3. The surface modification method according to claim 1, wherein the anti-migration blocking layer formed in the step S3 is a discrete phase layer having a thickness of 5-20 nm, and is distributed in a discontinuous particle phase in a cross-sectional direction.
  4. 4. The method of claim 1, wherein at least three incident orientations are combined with the autorotation of the substrate at 20-120 rpm in step S4.
  5. 5. The method of claim 1, wherein the bi-phase modulated bias signal of step S4 has a first phase bias voltage amplitude of 400-800 v, a second phase bias voltage amplitude of 200-500 v, and a first phase duration of 30% -50% of the entire period.
  6. 6. The surface modification method based on the ion implantation method according to claim 1, wherein the oxygen ion directional implantation in the step S5 is modulated by a pulse electric field of 5 to 20khz to induce formation of oxygen vacancy activation sites on the surface layer.
  7. 7. The surface modification method based on the ion implantation method according to claim 1, wherein the alternating electric field in the step S6 is applied in a bipolar symmetrical waveform, the period is 1-10S, and the duration of positive and negative potentials is equal to each other.

Description

Surface modification method based on ion implantation method Technical Field The invention relates to the technical field of surface modification, in particular to a surface modification method based on an ion implantation method. Background The metal implant such as titanium-based or cobalt-chromium-based material has good mechanical property and biocompatibility, and is widely used for long-term implantation in orthopaedics and stomatology. However, insufficient bioactivity, limited antimicrobial ability and poor long-term stability of the implant surface have been critical issues in clinical use. In order to improve the osteoinductive capacity and antibacterial property of the surface of the implant, the ion implantation technology gradually becomes a common surface modification means, and an active layer with bioactivity and antibacterial property can be constructed by implanting functional ions such as calcium, zinc, silver and the like into the surface of a metal matrix. However, the following non-negligible problems remain with existing ion implantation implants after exposure to prolonged body fluid environments. Firstly, chloride ions and protein complexes in body fluid can react with injected metal ions to promote migration, aggregation and redistribution of active ions such as Ca, zn, ag and the like, so that local high-concentration agglomerated phases are formed on the surface layer, and the risk of micro-galvanic corrosion is caused. Second, with the migration of the active ions, irreversible transformations of the chemical state of the implant surface may occur, such as acceleration of the hydration reaction of TiO 2 to Ti (OH) 4, altering the surface oxide structure, resulting in rapid decay of osteoinductive activity. Again, the outdiffusion and loss of implanted ions significantly shortens the effective retention time of antimicrobial ions, reduces early anti-infective ability after implantation, and causes a delay in bone integration process, which is detrimental to long-term implant stability. Therefore, a new ion implantation surface modification process is needed in the prior art to inhibit migration, agglomeration and chemical destabilization of active ions in body fluids while maintaining multi-ion functionality, thereby improving long-term biological stability and corrosion resistance of implants. Disclosure of Invention The invention aims to provide a surface modification method based on an ion implantation method so as to solve the problems. The invention provides a surface modification method based on an ion implantation method, which comprises the following steps: S1) surface pretreatment, namely mechanically polishing a titanium-based or cobalt-chromium-based implant, carrying out ultrasonic cleaning and carrying out inert gas plasma decontamination treatment to obtain a substrate surface with the surface roughness Ra less than or equal to 0.25 mu m; S2) forming an interface steady-state layer, namely pre-implanting low-energy nitrogen ions to form an inner layer interface steady-state layer, wherein the low-energy nitrogen ions are implanted at the energy of 30-80 keV and the dosage of 1X 10 16～5×1017ions/cm2, and the thickness of the steady-state layer is 20-80 nm; s3) forming an anti-migration blocking layer, namely performing low-concentration oxygen ion co-injection on the interface steady-state layer, wherein the energy is 5-15 keV, the dosage is 1 multiplied by 10 15～5×1015ions/cm2, and a discontinuous anti-migration blocking layer containing Ti-O-N or Cr-O-N sites is formed to inhibit inward diffusion of outer layer ions; s4) multicomponent functional ion implantation: sequentially implanting calcium ions, zinc ions and silver ions after the step S3, and performing implantation control by adopting a bi-phase modulation bias signal, wherein the bias amplitude of the first stage is 20-50V higher than that of the second stage; wherein the implantation energy of calcium ions is 40-80 keV, the dosage is 5 x 10 16～2×1017ions/cm2, The zinc ion implantation energy is 25-50 keV, the dosage is 2 x 10 16～1×1017ions/cm2, The implantation energy of silver ions is 10-25 keV, the dosage is 1X 10 15～5×1015ions/cm2, The depth gradient distribution structure of the calcium, zinc and silver from inside to outside is obtained through energy setting; S5) oxygen ion directional injection, namely implementing oxygen ion directional injection after the step S4, wherein the energy is 10-40 keV, the dosage is 2 multiplied by 10 16～8×1016ions/cm2, and a non-stoichiometric oxide layer with the oxygen/metal ratio of 1.2-1.8 is formed; S6) dynamic ion capturing aging, namely placing the injected workpiece in a water vapor environment with the temperature of 37-60 ℃ and the relative humidity of more than or equal to 90%, introducing phosphate buffer atmosphere with the equivalent of 0.05-0.50 mol/L for 24-48 h aging, applying an alternating electric field with the frequency of 0.1-1 Hz and the potent