[go: up one dir, main page]

WO2011083321A1 - Dispositif médical et procédé correspondant - Google Patents

Dispositif médical et procédé correspondant Download PDF

Info

Publication number
WO2011083321A1
WO2011083321A1 PCT/GB2011/000030 GB2011000030W WO2011083321A1 WO 2011083321 A1 WO2011083321 A1 WO 2011083321A1 GB 2011000030 W GB2011000030 W GB 2011000030W WO 2011083321 A1 WO2011083321 A1 WO 2011083321A1
Authority
WO
WIPO (PCT)
Prior art keywords
coating
process according
substrate
gas
range
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/GB2011/000030
Other languages
English (en)
Inventor
Bryan Greener
Hélène Anne LECOMTE
Darren James Wilson
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Smith and Nephew PLC
Original Assignee
Smith and Nephew PLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Smith and Nephew PLC filed Critical Smith and Nephew PLC
Publication of WO2011083321A1 publication Critical patent/WO2011083321A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C24/00—Coating starting from inorganic powder
    • C23C24/02—Coating starting from inorganic powder by application of pressure only
    • C23C24/04—Impact or kinetic deposition of particles

Definitions

  • the present invention relates to a process for coating a substrate and products formed thereby.
  • the present invention relates to a coating process comprising a gas dynamic spray process and medical products formed thereby.
  • Medical devices are fabricated from high grade/specification metals and alloys, which tend to be expensive.
  • stainless steel is a common material used in medical devices.
  • a problem associated with stainless steel is that it can be prone to infection, with infection rates of around 30% or higher reported.
  • Titanium is a common metal or alloy constituent used in medical devices. Titanium alloys, typically 6-aluminium-4 vanadium alpha-beta alloys ("Ti64", Ti-6%AI-4%), are widely used in medical devices due to unique properties such as: high resistance to many corrosive media including biological media; low specific weight as compared with stainless steel and copper alloys; high fatigue strength, the possibility of obtaining high (up to 100-120 kgf/mm 2 ) strength without the need of hardening by heat treatment; low irreversible energy-absorption level for ultrasonic vibrations, non-magnetizability, compatibility to bone cells due to high dielectric constant; and low incidence of infection.
  • Ti64 6-aluminium-4 vanadium alpha-beta alloys
  • Ti-6AI-4V 5 titanium alloy
  • the worldwide production of titanium ingots was approximately 64,000 tonnes in 2004, with the price of fabricated (i.e., mill products), chemically pure titanium being of the order of $ 3.60/lb (see Figure 1 ).
  • a process for coating a substrate comprising:
  • the coating material comprises powder particles and the gas dynamic spray process comprises impacting powder particles onto a substrate surface using a carrier gas, whereby the powder particles plastically deform thereby forming a coating on the substrate.
  • the velocity of the particles in the gas may be in the range 500 to 1500 m/s.
  • the velocity of the particles in the gas may be in the range 500 to 1250 m/s.
  • the velocity of the particles in the gas may be in the range 500 to 1000 m/s.
  • the particles may have a diameter in the range 1 to 50 microns.
  • the coating material may comprise at least one metal.
  • the metal may be selected from the group consisting of aluminium, copper, nickel, titanium, silver, zinc, tantalum, niobium, zirconium, tungsten, tantalum, cobalt, chromium, or combinations thereof.
  • the coating material may comprise titanium.
  • the coating material may comprise at least one metal alloy.
  • the metal alloy may be steel, Ni alloys or MCrAIYs.
  • the coating material may comprise at least one ceramic material.
  • the coating material may comprise at least one composite material.
  • the composite material may be Cu-W, Al-SiC or AI-AI2O3.
  • the coating material may comprise an active species.
  • the coating material may comprise a therapeutic agent.
  • the therapeutic agent may be selected from the group consisting of antibacterial agents, metals, antimicrobial agents, anticoagulants, antithrombotics, complement inhibitors, antiplatelet agents, antitumor agents, anti-inflammatories, enzymes, cytokines, catalysts, hormones, growth factors or inhibitors of growth factors, drugs, vitamins, antibodies, antigens, nucleic acids, dyes or other biological ligands, DNA, RNA, proteins, peptides, cells, stem cells, or combinations of any such therapeutic agents with each other and/or with adjuvants, and the like.
  • the carrier gas may be an inert gas.
  • the carrier gas may be selected from the group consisting of nitrogen, helium, air, or mixtures thereof.
  • the substrate may be a medical device.
  • the medical device may be an implant.
  • the coating may have a thickness in the range 0.1 ⁇ - 1 mm.
  • the coating may have a thickness in the range 0.1 ⁇ - 100 ⁇ .
  • the coating may have a thickness in the range 0.1 ⁇ - 50 ⁇ .
  • the coating may have a thickness in the range 0.1 ⁇ - 10 ⁇ ⁇ ⁇ .
  • the coating may have a thickness in the range 0.1 ⁇ - 5 ⁇ .
  • the coating may have a thickness in the range 0.5 ⁇ - 5 ⁇ .
  • a coated substrate formed by a process according to the first aspect of the present invention.
  • an implant formed by a gas dynamic spray process.
  • an implant comprising at least one first material coated with at least one second material.
  • an implant comprising a substrate coated with at least one material.
  • the coating may have a thickness in the range specified in the first aspect of the present invention.
  • Gas dynamic spray (also know as cold spray) technology in contrast to current fabrication technologies, has provided the potential for metals and alloys (for example titanium metal or its alloys) to be utilised in broader industrial applications and at lower cost.
  • Embodiments of the present invention relate to the coating of current orthopaedic medical devices with a layer of metal or alloy, such as titanium or its alloys. This has an advantage of limiting the opportunity for bacterial colonisation. This coating technique retains the prosthesis' bulk properties and reduces the overall manufacturing cost.
  • cold spraying various materials can be sprayed without exposing them (or the substrate) to high thermal loads.
  • the proposed technique allows coatings to be made with extremely low porosity and oxygen content.
  • the application efficiency is very high and can reach up to 90%.
  • both coating and substrate materials are subjected to oxidation, metallurgical transformations, and tensile residual stresses due to the elevated process temperature.
  • cold spray is capable of producing thick coatings that exhibit extremely low porosity ( ⁇ 0.5%), while avoiding oxidation, phase transformations, and tensile residual stresses for a wide selection of metals, cermets, and other material combinations.
  • the present invention provides coating resistance over other methods.
  • existing methods for coating titanium onto medical metals do not provide the interdigitation required for a strong coating, which will withstand insertion into bone.
  • current methods use a thermal firing step, which changes the structure of the underlying metal while applying titanium. This can lead to coatings delaminating while in use, due to the build-up of mechanical stress at the interface between the two metals.
  • Cold-spraying provides interdigitation between the coating and substrate metal, ensuring the spread of mechanical stresses and limiting the risk for delamination.
  • therapeutic agents may be included in the powder feedstock to generate antibacterial coatings via the gas dynamic spray (cold spray) process.
  • therapeutic agents can be added to the feed material (e.g. ceramics, metals, glasses) to produce a bioactive implant.
  • the powder and the therapeutic agent are carried by compressed air through a supersonic nozzle and sprayed onto the surface to be coated.
  • the therapeutic agent may be selected from the group consisting of: antibacterial agents; metals; antimicrobial agents; anticoagulants; antithrombotics; complement inhibitors; antiplatelet agents; antitumor agents; anti-inflammatories; enzymes; cytokines, catalysts; hormones; growth factors or inhibitors of growth factors; drugs; vitamins; antibodies; antigens; nucleic acids; dyes (which act as biological ligands); DNA and RNA; proteins and peptides; cells (such as stem cells), as well as combinations of any such therapeutic agents with each other and/or with adjuvants, and the like.
  • the coatings produced from cold spraying retain the antibacterial properties of the original feedstock powders.
  • the coating material is titanium or its alloys. Titanium is an important material of construction in orthopaedic applications.
  • Titanium has desirable properties, particularly in medical device applications, notably in relation to anti-infection.
  • the present invention provides cost advantages over other methods.
  • the titanium industry is being constrained by the extremely strong demand and tightness in the supply of raw materials needed to produce titanium mill products for medical devices.
  • the driving force behind this increased demand is the growth of the orthopaedic market forecasted to rise by 9.8% annually to $23 billion in 2012. This is likely to lead to lower supplies to the orthopaedic industry due to the increased prices, and a dampened enthusiasm for titanium in new markets where it offers substantial long-term cost savings.
  • Titanium alloys are also more costly than other medical metals such as cobalt-chrome alloys or stainless steel.
  • the invention allows coating of a prosthesis made of a less costly metal with only a coating layer of resistant titanium alloy, which provides a cost advantage compared to a whole prosthesis made of titanium.
  • Other advantages include (a) reduction in material input, (b) elimination of mold and melt pour cost, (c) reduction in rework, (d) reduction in finishing costs, and (e) large increase in material utilization (cold spray typically has deposition efficiency of 60-95%, and can exceed 99%).
  • the amount of titanium powder used during spray coating of the device is approximately 10-15g at a cost of £80/kg taking into account the cost of the equipment. It would cost less than $10 to apply a 200 micron thick coating onto the external surface of the device based on a realistic deposit rate of 1-2 kg/hour.
  • Metallic medical implants such as orthopaedic devices (reconstruction, trauma, spinal), can support the development of infections after surgery. Infection develops onto metallic surfaces because these provide a nidus for bacteria to attach and proliferate. Infection from metallic implants can have devastating consequences for the patient, going from implant loosening and simple prosthesis exchange with antibiotic treatment, to spreading osteomyelitis and septicaemia.
  • peri-prosthetic infections PPI
  • osseointegration is required, is that bacteria win the race for the surface of the implant.
  • competition for cell attachment occurs between osteoblasts or other human cells, and bacterial cells.
  • bacterial cells win this race, they can adhere to the implant surface, and start proliferating, culminating in the formation of a biofilm which prevents the eventual osseointegration of the prosthesis.
  • osseointegration such as spinal rods, osteosynthesis plates, ex fix pins, screws, and intramedullary nails
  • areas of the device remain largely unchecked by the immune system or the blood flow, as they sit out of the bone area: these become easier targets for bacterial cell adhesion.
  • antibiotic- loaded bone cement can also be used in some indications with relevant orthopaedic prosthesis (e.g. cemented knee femoral component, cemented hip stem).
  • relevant orthopaedic prosthesis e.g. cemented knee femoral component, cemented hip stem.
  • Gosheger et al J. Arthroplasty 2008; 23:916-20
  • Gosheger et al performed a retrospective clinical study of 197 patients with a megaprosthesis of the lower extremity made either of Co-Cr alloy or Ti alloy. They found that the overall infection rate associated with the prosthesis was 31 % of those patients with Co-Cr metal, and 14% of those patients with Ti metal.
  • Table 1 Summary of trends in infection rate in the pre-clinical and clinical papers cited.
  • Literature highlights the fact that titanium implants may be better at resisting bacterial colonisation and promoting osseointegration compared to other metals. Ti alloy implants are already available from a number of manufacturers, but their major drawback is their cost of manufacture (reflected in the implant asking price).
  • Cold gas-dynamic spraying is a high-rate material deposition process which can be used to coat a variety of metals/alloys (for example titanium alloys) onto the surface of a metallic medical device.
  • the cold spray process uses the energy stored in high pressure compressed gas to propel fine powder particles (typically 1 to 50 pm) at very high velocities (typically 600 m/s, but can be anywhere between 500 and 1500 m/s).
  • Compressed helium gas is fed via a heating unit to the gun where the gas exits through a nozzle at very high velocity.
  • Compressed gas is also fed via a high pressure powder feeder to introduce powder material into the high velocity gas jet.
  • the powder particles are accelerated and moderately heated (for example, ⁇ 60 °C) to a certain velocity and temperature where on impact with a substrate they plastically deform disrupting the metal oxide providing intimate conformal contact between the clean metal surfaces under high local pressure. This permits bonding to occur and layers of deposited metal to build up rapidly. Given that many joint replacements have textured surfaces to encourage bone ingrowth through grit or bead blasting, this improves the deposition efficiency of the metallic powders.
  • the deposition efficiency for cold spraying is typically greater than 99%, which exceeds the maximum achieved with vacuum plasma spray processes (65%, see “Hao Du et al. Effect of plasma spraying conditions on deposition efficiency, microstructure and microhardness of Ti02 coating, Azojomo, Journal of Materials Online, 2005, Volume 1 , September, pp 1 -12", or “Hao Du et al. Effect of plasma spraying conditions on deposition efficiency, microstructure and microhardness of Ti02 coating, Advances in Technology of Materials and Materials Processing, 6[2] (2004) 152-157)”).
  • a fine balance between particle size, density, temperature and velocity are important criteria to achieve the desired coating which can vary between 0.1 ⁇ and 1 mm.
  • the particles remain in the solid state and are relatively cold, so the bulk reaction on impact is solid state only.
  • the process imparts little to no oxidation to the spray material, so surfaces stay clean which aids bonding.
  • No melting and relatively low temperatures result in very low shrinkage on cooling.
  • the low operating temperature also aids in retaining the original powder chemistry and phases in the coating, with only changes due deformation and cold working.
  • the temperature is lower than the melting point of the feedstock powder (typically ambient temperature to 700°C). This is in contrast with thermal spraying where the coating readily oxidises due to the higher operating temperature.
  • the coating technique is ideally suited to ductile materials (Al, Cu, Ni, Ti, Ag, Zn, Ta, Nb) and alloys (stainless steel, and cobalt chromium) commonly used in the medical industry.
  • ductile materials Al, Cu, Ni, Ti, Ag, Zn, Ta, Nb
  • alloys stainless steel, and cobalt chromium
  • Figure 1 shows consumption versus cost for various materials [reproduced from T.E. Norgate and G. Wellwood, The Potential Applications for Titanium Metal Powder and Their Life Cycle Impacts, JOM, P58, 2006];
  • Figure 2 shows a gas dynamic spray (cold spray) equipment setup for additive fabrication
  • Figure 3 shows a process map for using gas dynamic spray (cold spray) coatings with joint replacement devices
  • Figure 4 shows a process map for using gas dynamic spray (cold spray) coatings with trauma fixation devices
  • Figure 5 shows data for raster runs R1-U, R2-H and R2-U;
  • Figure 6 shows data for raster runs R2-X and R2-Y
  • Figure 7 shows data for raster runs R2-Z and R2-AA
  • Figure 8 shows data for raster runs R2-BB and R2-BB'
  • Figure 9 shows data for raster runs R3-1 and R4-1 ;
  • Figure 10 shows the location of indentations for runs R03-3 and R04-3;
  • Figure 11 shows data for run R03-3;
  • Figure 12 shows data for run R04-3
  • Figure 13 shows a metallographic section of a pin taken radially;
  • Figure 14 shows a metallographic section of a pin taken axially;
  • Figure 15 shows un R05, as-sprayed;
  • Figure 16 shows un R05, post bead-blasted
  • Figure 17 shows un R06, as-sprayed
  • Figure 18 shows un R06, post bead-blasted
  • Figure 9 shows un R07, as-sprayed
  • Figure 20 shows un R07, post bead-blasted
  • Figure 21 shows un R08, as-sprayed
  • Figure 22 shows un R08, post bead-blasted
  • Figure 23 shows un R09, as-sprayed
  • Figure 24 shows un R09, post bead-blasted
  • Figure 25 shows un R 0, as-sprayed and post bead-blasted
  • Figure 26 shows un R 1 , as-sprayed and post bead-blasted
  • Figure 27 shows un R 2a (fine bead).
  • Figure 28 shows un R12b (fine bead)
  • Figure 29 shows un R12c (fine bead)
  • Figure 30 is a bar chart showing mean normalised alkaline phosphatase to
  • Figure 31 is a bar chart showing normalised alkaline phosphatase (with non- osteogenic baseline subtracted).
  • the major components of a commercial cold spray system include (a) 6-axis robot- mounted spray gun, which controls the optimal positioning of the spray gun relative to the surface of the implant (typically 90°), (b) gas control system which uses either Nitrogen or Helium, (c) powder feed unit, (d) waste particle collection unit, and (e) heater unit.
  • the components of the cold spray equipment are outlined in Figure 2.
  • the process gas is introduced to a manifold system containing a gas heater and powder-metering device.
  • the pressurized gas is heated to a preset temperature, often using a coil of an electrical resistance-heated tube.
  • the gas is heated not to heat or soften spray particles, but instead to achieve higher flow velocities, which ultimately result in higher particle impact velocities.
  • the high-pressure gas is introduced into the entrance of a nozzle (converging/diverging or converging only), where the gas accelerates to high velocity as it expands in the nozzle.
  • the gas cools as it expands in the spray nozzle, sometimes exiting the spray gun at below ambient temperature.
  • the powder to be deposited is introduced by a separate gas stream either at the nozzle entrance or at a lower pressure location on the nozzle, where the powder mixes with the main gas stream and is accelerated by the gas stream.
  • the process gas may be (but not restricted by) any of the following: a. Nitrogen (N 2 ), b. Helium (He), c. Mixture of Nitrogen and Helium (N 2 + He), and d. Air.
  • the gas is used to improve deposition performance and material functionality and ensure economic viability.
  • the powder for coating is preferably dry, free flowing, and thoroughly blended. Mixtures of powder stock with varying density and/or size particulates are preferably kept from settling or stratifying in the feeder as long as that powder charge is utilized.
  • the mass median particle size is preferably between 5 and 100 ⁇ in diameter.
  • Typical operating parameters may be as follows:- gas pressure (MPa) 2.5-4.5 MPa, gas pre-heat 20-800°C, gas flow rate 50-150 m 3 /hour, powder flow rate 0.1-1.0 g/s.
  • the substrate that is coated is a medical device such as an implant. Accordingly, embodiments of the present invention can find application in orthopaedic devices, including joint reconstruction devices and trauma fixation devices.
  • Figure 2 shows a nail and a magnified cross-section of a portion of the coated nail, showing the substrate, interface and Ti coating (the scale bar on the sample image is 500 pm).
  • Figures 3 and 4 show process maps exemplifying such joint reconstruction devices and trauma fixation devices, respectively.
  • the gas dynamic/cold spray process can be applied to the bearing surfaces of metal-on metal total joint replacements in such areas as improved wear, corrosion protection and reduced cobalt and chromium ion sensitivity. They can also be applied to other trauma devices such as ex fix pins and percutaneous devices where bacterial colonisation is more prevalent. Cold spray coatings are also beneficial where electromagnetic interference shielding is required, such as electronic packaging devices or repair of damaged components. Examples
  • the coatings were produced on a stainless steel substrate.
  • the coatings had a uniform appearance consistent with line of sight type processing without any bare areas discernable at x5 magnification.
  • the coatings had a bond strength greater than 34 MPa (typically achieved for vacuum plasma spraying HA onto metal) and was determined in accordance with IS013779-4 or ASTM F1147-05.
  • sample coatings were deposited onto 316 stainless steel square coupons (25x25x5 mm) and discs (25.4 mm diameter; 5 mm thickness).
  • the samples were ultrasonically cleaned with acetone prior to use and given a final clean using acetone to remove any surface residue introduced whilst mounting the samples for spraying.
  • test coupons were mounted in individual fixtures and stationary whilst a spray gun raster scanned across them. Powder type and feed rate, gun off-set, gun scanning velocity, and substrate top surface preparation were varied. Coating thickness (and relative tolerance) was the primary method of assessing whether selected process parameters were suitable. Metallographic sections were used to appraise the coating/substrate interface and consolidation of the deposit.
  • Table 5 - Spray Runs (2) Trials on flat coupons using a turntable were also performed. Test coupons were mounted in individual fixtures on a turntable. The rotational speed of the turntable and vertical scanning velocity of the cold spray gun were adjusted to achieve the desired linear spraying velocities and off-sets for each sample. All substrates were grit-blasted to provide mechanical keying for a coating to build on. To provide more accurate control over the grit blasting process, it was conducted by feeding mesh size 180/220 Al 2 0 3 through the cold spray system itself. LPW powder (LPW Technology Ltd) was used for all the spray runs.
  • Figures 5 to 9 show sample images, spray parameters (PFR (powder flow rate); gun off- set; gun scan speed; scan program) and coating thickness (mean and standard deviation) for various raster runs.
  • Figure 5 shows data for raster runs R1-U, R2-H and R2-U. The scale bar shown in the sample image of figure 5 is 250 pm (and applies to the sample images shown in figures 6 to 9).
  • Figure 6 shows data for raster runs R2-X and R2-Y.
  • Figure 7 shows data for raster runs R2-Z and R2-AA.
  • Figure 8 shows data for raster runs R2-BB and R2-BB'.
  • Figure 9 shows data for raster runs R3-1 and R4-1. Raster PFR Gun Gun Substrat Powde Post
  • Runs R03 and R04 were used to produce test coupons for assessing the properties of the deposit.
  • SR Spray rate
  • DR deposit rate
  • DE deposition efficiency
  • Coating adhesion was measured according to ASTM F1147-05 ("Standard Test Method for Tension Testing of Calcium Phosphate and Metallic Coatings"). For each test, cold spray coatings were deposited onto three 316 stainless steel discs (1 " in diameter). These were bonded to the face of an uncoated sample holder, which was grit blasted to effect a good adhesive bond. Araldite AV119 epoxy based adhesive was used to bond the coated discs and uncoated studs together. The bonded assembly was then subjected to tensile loading normal to the plane of the coating. A servo-hydraulic testing machine was used to apply load, to failure of the bonded joint. The maximum load required to pull the coatings away from the substrates was measured for each test. Following test, the specimens were examined to determine the location of failure. The results of all the adhesive bond tests are presented as failure stress, together with the standard deviations from the mean.
  • Figures 1 1 and 12 show sample images and microstructure, hardness and roughness data for runs R03-3 and R04-3.
  • the scale bar shown in the sample images of figures 11 and 12 is 50 pm.
  • Figure 13 shows a metallographic section of an HA (hydroxyapatite) coated pin taken radially.
  • the scale bar shown in the image is 250 pm.
  • the coating thickness is 53+/-18 pm.
  • Figure 14 shows a metallographic section of a HA coated pin taken axially.
  • the scale bar shown in the image is 500 pm.
  • the coating thickness is 37+/-4 pm.
  • Figure 15 shows run R05 as-sprayed.
  • the scale bar In the left-hand image, the scale bar is 1000 pm. In the right-hand image, the scale bar is 250 pm.
  • Figure 16 shows run R05 post bead-blasted. In the left-hand image, the scale bar is 1000 ⁇ and the coating thickness is 40+/-13 ⁇ . As can be seen, the diagonal edge is partially coated and the vertical edge is not coated. In the right-hand image, the scale bar is 250 pm.
  • Figure 17 shows run R06 as-sprayed.
  • the scale bar In the left-hand image, the scale bar is 1000 m. In the right-hand image, the scale bar is 250 ⁇ .
  • Figure 18 shows run R06 post bead-blasted. In the left-hand image, the scale bar is 1000 pm and the coating thickness is 72+/-17 ⁇ As can be seen, the diagonal edge is coated and the vertical edge is not coated. In the right-hand image, the scale bar is 250 ⁇ .
  • Figure 19 shows run R07 as-sprayed.
  • the scale bar is 1000 pm and the coating thickness is 59+1-27 pm.
  • the diagonal edge is partially coated and the vertical edge is not coated.
  • the scale bar is 250 ⁇ .
  • Figure 20 shows run R07 post bead-blasted.
  • the scale bar is 1000 pm and the coating thickness is 59+/-2 ⁇ pm.
  • the diagonal edge is partially coated and the vertical edge is not coated.
  • the scale bar is 250 pm.
  • Figure 21 shows run R08 as-sprayed.
  • the scale bar In the left-hand image, the scale bar is 1000 pm and the coating thickness is 48+/-19 pm. As can be seen, the diagonal edge is marginally coated and the vertical edge is marginally coated.
  • the scale bar In the right-hand image, the scale bar is 250 ⁇ and the coating thickness is 68+/-19 ⁇ .
  • Figure 22 shows run R08 post bead-blasted.
  • the scale bar In the left-hand image, the scale bar is 1000 ⁇ and the coating thickness is 33+/-13 ⁇ . As can be seen, the diagonal edge is marginally coated and the vertical edge is marginally coated.
  • the scale bar In the right-hand image, the scale bar is 250 ⁇ and the coating thickness is 73+/-16 ⁇ .
  • Figure 23 shows run R09 as-sprayed. In the left-hand image, the scale bar is 1000 pm and the coating thickness is 87+/-23 pm. As can be seen, the diagonal edge is coated and the vertical edge is coated. In the right-hand image, the scale bar is 250 pm and the coating thickness is 101 +/- 7 pm.
  • Figure 24 shows run R09 post bead-blasted.
  • the scale bar is 1000 pm and the coating thickness is 75+/-19 pm.
  • the diagonal and vertical edges are coated, but the top edge is de-bonded.
  • the scale bar is 250 pm and the coating thickness is 69+/-16 pm.
  • Figure 25 shows run R 0.
  • the left-hand image shows post bead-blasted.
  • the scale bar is 1000 pm and the coating thickness is 278+/-11 pm.
  • the right-hand image shows as- sprayed.
  • the scale bar is 1000 pm and the coating thickness is 250+/-65 pm. As can be seen, the diagonal and vertical edges are coated.
  • Figure 26 shows run R1 1.
  • the left-hand image shows post bead-blasted.
  • the scale bar is 250 pm and the coating thickness is 176+/- 8 pm.
  • the right-hand image shows as- sprayed.
  • the scale bar is 250 pm and the coating thickness is 151 +/-42 pm. As can be seen, the diagonal and vertical edges are coated.
  • Figure 27 shows run R12a (fine bead; 30 psi; 2 passes).
  • the top image scale bar is 1000 pm and the coating thickness is 156+/-13 pm.
  • the bottom image scale bar is 250 pm.
  • Figure 28 shows run R12b (fine bead; 30 psi; 1 pass).
  • the top image scale bar is 1000 pm and the coating thickness is 151+/-24 pm.
  • the bottom image scale bar is 250 pm.
  • Figure 29 shows run R12c (fine bead; 40 psi; 2 passes).
  • the top image scale bar is 1000 pm and the coating thickness is 154+/-14 pm.
  • the bottom image scale bar is 250 pm.
  • Figures 30 and 31 show in vitro bone mineralisation (expressed in terms of ALP (Alkaline Phosphatase) production) data generated from a series of metal surfaces.
  • “Ost” means osteogenic cell culture media and “N/O” means non-osteogenic cell culture media.
  • TCP tissue culture plastic (positive control).
  • SS is stainless steel.
  • Ti R16 Ost exemplifies the present invention and is CP (commercially pure) Ti cold sprayed onto stainless steel tested in osteogenic cell culture media.
  • Ti G5" is Ti grade 5 alloy.
  • i G2 is Ti grade 2 (CP) commercially pure metal.
  • HAp is hydroxyapatite.
  • Pin deflection during deposition affects the length of coating deposited on the smooth section of the pin (from 50 to 30 mm) by changing the holding point in the lathe chuck.
  • Optimising the bead blasting conditions reduces the amount of damage of the coating.
  • Three S&N HEX FIX half pins R13, R14 and R15 were produced. These were coated using the spray and bead-blasting conditions specified for R12c.
  • the attached data has shown that a Ti barrier can be deposited onto stainless steel threaded pins using a cold spray process. The morphology or size distribution of the Ti powder may be controlled in order to optimise the process and product formed thereby.
  • the bead material e.g. ceramic bead, Zr0 2
  • blasting conditions may be varied.
  • Ti could be co-deposited with a hard-phase material (for example HA).
  • the nozzle design may be varied in order to modify the deformation of Ti during deposition.
  • the porosity of the final coating can be varied from minimal porosity to medium or high porosity (typically 70%), desirable for Trauma and Recon implants, respectively.
  • porogens may be included in the feedstock to increase porosity as desired.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Materials For Medical Uses (AREA)

Abstract

L'invention porte sur un procédé pour le revêtement d'un substrat, consistant à : se procurer un substrat ; se procurer un produit de revêtement ; appliquer le produit de revêtement en revêtement sur le substrat par un procédé de projection dynamique par gaz. L'invention porte également sur un substrat revêtu formé par un tel procédé. L'invention porte également sur un implant formé par un tel procédé de projection dynamique par gaz.
PCT/GB2011/000030 2010-01-11 2011-01-11 Dispositif médical et procédé correspondant Ceased WO2011083321A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB1000399.4 2010-01-11
GB201000399A GB201000399D0 (en) 2010-01-11 2010-01-11 Medical device and method

Publications (1)

Publication Number Publication Date
WO2011083321A1 true WO2011083321A1 (fr) 2011-07-14

Family

ID=41819183

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB2011/000030 Ceased WO2011083321A1 (fr) 2010-01-11 2011-01-11 Dispositif médical et procédé correspondant

Country Status (2)

Country Link
GB (1) GB201000399D0 (fr)
WO (1) WO2011083321A1 (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130029173A1 (en) * 2011-07-27 2013-01-31 Northrop Grumman Systems Corporation Coatings for Protection Against Corrosion in Adhesively Bonded Steel Joints
WO2013044746A1 (fr) * 2011-09-30 2013-04-04 先健科技(深圳)有限公司 Procédé de préparation d'un revêtement composite qui contient du cuivre sur une partie métallique d'un dispositif médical et dispositif médical
WO2013149291A1 (fr) * 2012-04-04 2013-10-10 Commonwealth Scientific And Industrial Research Organisation Procédé de fabrication d'une structure de support de charge en titane
WO2018067086A3 (fr) * 2016-08-12 2018-05-17 Istanbul Teknik Universitesi Procédé de production d'un revêtement épais à structure stratifiée
GR20200100685A (el) * 2020-11-18 2022-06-08 Πυρογενεσις Αβεε, Μεθοδος για προσδεση χημικων ενωσεων πανω σε στερεες επιφανειες με χρηση θερμου ψεκασμου κονεων / θερμων σωματιδιων και σχηματισμο πηκτωματων
CN115120783A (zh) * 2022-06-29 2022-09-30 湖南华翔医疗科技有限公司 一种多孔钛基抗菌活性材料及制备方法与应用

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5302414A (en) * 1990-05-19 1994-04-12 Anatoly Nikiforovich Papyrin Gas-dynamic spraying method for applying a coating
WO2003039407A2 (fr) * 2001-11-09 2003-05-15 Biocompatibles Limited Procede de realisation de tuteur endovasculaire
US20030219542A1 (en) * 2002-05-25 2003-11-27 Ewasyshyn Frank J. Method of forming dense coatings by powder spraying
US20090118815A1 (en) * 2007-11-02 2009-05-07 Boston Scientific Scimed, Inc. Stent

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5302414A (en) * 1990-05-19 1994-04-12 Anatoly Nikiforovich Papyrin Gas-dynamic spraying method for applying a coating
US5302414B1 (en) * 1990-05-19 1997-02-25 Anatoly N Papyrin Gas-dynamic spraying method for applying a coating
WO2003039407A2 (fr) * 2001-11-09 2003-05-15 Biocompatibles Limited Procede de realisation de tuteur endovasculaire
US20030219542A1 (en) * 2002-05-25 2003-11-27 Ewasyshyn Frank J. Method of forming dense coatings by powder spraying
US20090118815A1 (en) * 2007-11-02 2009-05-07 Boston Scientific Scimed, Inc. Stent

Non-Patent Citations (8)

* Cited by examiner, † Cited by third party
Title
ARENS ET AL., JBJS [BR], vol. 78-B, 1996, pages 647 - 51
AZOJOMO ET AL.: "Hao Du et al. Effect of plasma spraying conditions on deposition efficiency, microstructure and microhardness of Ti02 coating", JOURNAL OF MATERIALS ONLINE, vol. 1, September 2005 (2005-09-01), pages 1 - 12
CORDERO ET AL., JBJS [BR], vol. 76-B, 1994, pages 717 - 20
GOSHEGER ET AL., J. ARTHROPLASTY, vol. 23, 2008, pages 916 - 20
HAO DU ET AL.: "Effect of plasma spraying conditions on deposition efficiency, microstructure and microhardness of Ti02 coating", ADVANCES IN TECHNOLOGY OF MATERIALS AND MATERIALS PROCESSING, vol. 6, no. 2, 2004, pages 152 - 157
J. SURG. ORTHOP. ADV., vol. 17, no. 3, 2008, pages 193 - 9
SOULTANIS ET AL., STUD. HEALTH TECHNOL. INFORM., vol. 123, 2006, pages 559 - 64
T.E. NORGATE; G. WELLWOOD: "The Potential Applications for Titanium Metal Powder and Their Life Cycle Impacts", JOM, 2006, pages 58

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9422459B2 (en) * 2011-07-27 2016-08-23 Northrop Grumman Systems Corporation Coatings for protection against corrosion in adhesively bonded steel joints
US20130029173A1 (en) * 2011-07-27 2013-01-31 Northrop Grumman Systems Corporation Coatings for Protection Against Corrosion in Adhesively Bonded Steel Joints
WO2013044746A1 (fr) * 2011-09-30 2013-04-04 先健科技(深圳)有限公司 Procédé de préparation d'un revêtement composite qui contient du cuivre sur une partie métallique d'un dispositif médical et dispositif médical
US9765435B2 (en) 2012-04-04 2017-09-19 Commonwealth Scientific And Industrial Research Organisation Process for producing a titanium load-bearing structure
CN104364018A (zh) * 2012-04-04 2015-02-18 联邦科学与工业研究组织 一种用于生产钛承重结构的方法
AU2013243224B2 (en) * 2012-04-04 2017-09-14 Commonwealth Scientific And Industrial Research Organisation A process for producing a titanium load-bearing structure
WO2013149291A1 (fr) * 2012-04-04 2013-10-10 Commonwealth Scientific And Industrial Research Organisation Procédé de fabrication d'une structure de support de charge en titane
AU2013243224C1 (en) * 2012-04-04 2018-02-01 Commonwealth Scientific And Industrial Research Organisation A process for producing a titanium load-bearing structure
US10378112B2 (en) 2012-04-04 2019-08-13 Commonwealth Scientific And Industrial Research Organisation Process for producing a titanium load-bearing structure
WO2018067086A3 (fr) * 2016-08-12 2018-05-17 Istanbul Teknik Universitesi Procédé de production d'un revêtement épais à structure stratifiée
DE112017004063B4 (de) 2016-08-12 2022-06-02 Istanbul Teknik Universitesi Verfahren zur Herstellung einer Dickbeschichtung mit schichtweisem Aufbau
GR20200100685A (el) * 2020-11-18 2022-06-08 Πυρογενεσις Αβεε, Μεθοδος για προσδεση χημικων ενωσεων πανω σε στερεες επιφανειες με χρηση θερμου ψεκασμου κονεων / θερμων σωματιδιων και σχηματισμο πηκτωματων
CN115120783A (zh) * 2022-06-29 2022-09-30 湖南华翔医疗科技有限公司 一种多孔钛基抗菌活性材料及制备方法与应用

Also Published As

Publication number Publication date
GB201000399D0 (en) 2010-02-24

Similar Documents

Publication Publication Date Title
Singh et al. Deposition of HA-TiO2 by plasma spray on β-phase Ti-35Nb-7Ta-5Zr alloy for hip stem: Characterization, mechanical properties, corrosion, and in-vitro bioactivity
Singh et al. Influence of post coating heat treatment on microstructural, mechanical and electrochemical corrosion behaviour of vacuum plasma sprayed reinforced hydroxyapatite coatings
Mohseni et al. Comparative investigation on the adhesion of hydroxyapatite coating on Ti–6Al–4V implant: A review paper
Liu et al. Plasma sprayed wollastonite/TiO2 composite coatings on titanium alloys
Singh et al. Characterization and mechanical behaviour of reinforced hydroxyapatite coatings deposited by vacuum plasma spray on SS-316L alloy
EP2435602B1 (fr) Procédé de revêtement
WO2011083321A1 (fr) Dispositif médical et procédé correspondant
Gogheri et al. Mechanical properties, corrosion behavior and biocompatibility of orthopedic pure titanium− magnesium alloy screw prepared by friction welding
Singh et al. Synthesis and characterization of plasma sprayed functional gradient bioceramic coating for medical implant applications
Singh et al. Characterization of thermal sprayed hydroxyapatite coatings on some biomedical implant materials
Khanna et al. Fabrication of dense α-alumina layer on Ti-6Al-4V alloy hybrid for bearing surfaces of artificial hip joint
Khor et al. Ti-6Al-4V/hydroxyapatite composite coatings prepared by thermal spray techniques
Fuerst et al. LASER additive manufacturing of titanium-tantalum alloy structured interfaces for modular orthopedic devices
Ng et al. Mechanical reliability modification of metal matrix composite coatings by adding al particles via cold spray technology
Lu et al. Microstructural inhomogeneity in plasma-sprayed hydroxyapatite coatings and effect of post-heat treatment
Hahn et al. Preparation and in vitro characterization of aerosol-deposited hydroxyapatite coatings with different surface roughnesses
Morks et al. Abrasive wear behavior of sprayed hydroxyapitite coatings by gas tunnel type plasma spraying
Singh et al. Study on the morphological and mechanical properties of TaC reinforced plasma spray coating deposited on titanium alloy
Lee et al. A Nitinol structure with functionally gradient pure titanium layers and hydroxyapatite over-coating for orthopedic implant applications
Fujisawa et al. The development of new titanium arc-sprayed artificial joints
CN108728844A (zh) 一种医用生物涂层的冷喷涂制备方法
Baloyi et al. Laser coating of zirconium and ZrO2 composites on Ti6Al4V for biomedical applications
Nadian et al. Innovative plasma spray coating of HA-Ti-MgO composite on Ti6Al4V alloy for enhanced performance
Mrdak et al. Characterisation of biocompatible layers of ZrO28% Y2O used in combination with other ceramics to modify the surface of implants
Singh Mechanical behavior of plasma-sprayed pure and reinforced hydroxyapatite coatings on Ti6Al4V alloy

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 11702274

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 11702274

Country of ref document: EP

Kind code of ref document: A1