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
  • C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
  • C23C4/18—After-treatment
• • 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
• • 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
  • C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
  • C23C28/30—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer
  • C23C28/32—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer
  • C23C28/321—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one pure metallic layer with at least one metal alloy layer
• • 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
  • C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
  • C23C28/30—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer
  • C23C28/34—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates
• • 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
  • C23C28/00—Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of groups C23C2/00 - C23C26/00 or by combinations of methods provided for in subclasses C23C and C25C or C25D
  • C23C28/30—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer
  • C23C28/34—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates
  • C23C28/341—Coatings combining at least one metallic layer and at least one inorganic non-metallic layer including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates with at least one carbide layer
• • 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
  • C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
  • C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases

Definitions

• the invention relates to a method for modifying a substrate by forming a diffusion layer, a material thus obtained, its use and a product comprising the material according to the invention.
• Coatings are essential in all technical areas. They can achieve functional improvements or increase the life of workpieces and components. They are used for wear protection, titanium fire protection, thermal insulation, corrosion and oxidation protection, as rubbing and sealing coverings, erosion protection and as dimensional correction coatings. For this reason, for example, 50% of all components are coated in aviation. Essentially layers or coated components are used against wear, corrosion, hot gas corrosion and oxidation, titanium fire and layers or coated components to minimize the gap between rotor and stator and for thermal insulation.
• the WO-A-2005/045102 discloses the coating of a metallic substrate by electrodeposition of one or more layers containing at least one metal and / or one metal alloy.
• the outermost galvanic layer consists of aluminum, magnesium, tin or mixtures thereof and / or alloys thereof.
• the outermost layer contains an aluminum / magnesium and / or an aluminum / tin alloy.
• Also disclosed is the formation of one or more intermediate layers Metals selected from the group iron, iron / nickel, tin / nickel, nickel, cobalt, copper, chromium, molybdenum, vanadium or alloys of these metals.
• the heat treatment takes place at a temperature of 400 to 1000 ° C.
• the document discloses the electrodeposition of the individual layers, followed by a further step of the heat treatment.
• the WO-A-2006/013184 discloses a method for producing coated workpieces from a light metal or a light metal alloy, said method comprising electrodepositing one or more layers of at least one metal or metal alloy selected from the group consisting of aluminum, magnesium and zinc, and the following Heat treatment at 200 ° C to 800 ° C. More specifically, the document discloses two embodiments, namely the coating of an aluminum or aluminum alloy substrate with an intermediate layer of magnesium, zinc or an alloy thereof, followed by an outer layer of aluminum, magnesium or an alloy thereof. In another embodiment, the document discloses coating a magnesium or magnesium alloy substrate with an intermediate layer of aluminum, zinc or an alloy thereof, followed by an outer layer of aluminum, magnesium, zinc or an alloy of these metals.
• workpieces with complex topographies and geometries should be able to be coated without the so-called dogbone effect (excessive layer structure, especially in the edge / corner area), which causes problems, in particular in the case of galvanic coatings.
• the diffusion heat treatment according to the invention is a thermal treatment in which it comes to interdiffusion, ie the diffusion of the elements of the individual layers and the substrate-near layers and the substrate, whereby a diffusion layer is formed, which includes both elements of the substrate and elements of the coating having.
• the diffusion layer is defined by the state which, due to the method according to the invention, is established by the interdiffusion associated with the method.
• the diffusion layer is one or more mixed crystal layers and / or one or more intermetallic phases.
• the diffusion layer may have a gradient layer structure in which the composition changes continuously along an axis perpendicular to the surface.
• the diffusion layer may have a homogeneous element distribution.
• the diffusion layer can only form an edge region of the material or alternatively comprise the entire material.
• SDM Shape-Deposition-Manufacturing
• Spray methods suitable in the invention are thermal spraying and cold gas spraying, with cold gas spraying being particularly preferred.
• cold gas spraying With the help of cold gas spraying and metal layers can be sprayed, which can be applied with other spraying difficult, as it comes under the conditions increasingly for the oxidation of the metals to be applied.
• the cold gas spraying is therefore particularly preferred when applying ductile Metals where oxidation is particularly undesirable.
• oxidation deteriorates the adhesion of the coated layer to the substrate.
• Particularly suitable is the cold gas spraying in the application of copper, for example on CPU primaleitblechen.
• the application of aluminum by cold gas spraying which is carried out at a temperature of 200 to 500 ° C.
• the coating material is applied to the substrate in powder form at very high speed at temperatures below its melting point.
• a heated to only a few hundred ° C process gas is accelerated to supersonic speed and then the powder particles are injected into the gas jet.
• the injected spray particles are thereby accelerated to such a high speed that, in contrast to other thermal spraying methods, they form a dense and firmly adhering layer upon impact with the substrate even without prior melting or melting.
• the kinetic energy at the time of impact is insufficient for complete melting of the particles.
• Thermal spraying includes flame spraying (especially wire flame spraying, powder flame spraying), electric arc spraying, laser spraying, detonation spraying (also called flame shock spraying), plasma spraying and high velocity flame spraying.
• the wire-shaped spray additive is melted with a fuel gas-oxygen flame and injected by the combustion gas alone onto the component surface.
• powder flame spraying working with powdered spray additives.
• a wire or filler wire spray additive is melted in an electric arc and thrown onto the component surface through a nebulizer gas (air).
• the electric arc is generated between the two wire ends by applying a voltage and contact ignition.
• Flame-squirt uses the energy released by controlled detonations of oxygen and gas mixtures to heat and accelerate powder particles.
• the powdery coating material is introduced by means of a carrier gas into a high-energy plasma jet, which is melted by the high plasma temperature.
• the plasma gas stream entrains the powder particles and throws them onto the substrate to be coated.
• the coating material is not applied by plasma spraying.
• High-velocity flame spraying HVOF - High Velocity Oxy Fuel
• the powdery spray material is melted evenly and fired at the surface to be coated with very high kinetic energy.
• Carrier gas is often nitrogen.
• the flattening of the spray particles on impact leads to fine-grained layers with low porosity, which have only low internal residual stresses and high adhesive tensile strengths, which layers can be sprayed with very large thickness. Because of the low particle temperature compared to other thermal spraying processes, the layers are nearly homogeneous and have a very low oxide content.
• all applied layers are sprayed and / or applied by means of shape-deposition-manufacturing.
• the metallic layer applied last is referred to below as the outer layer.
• the other metallic layers are referred to as intermediate layers, wherein the first, d. H. directly applied to the substrate metallic layer can be referred to as the first intermediate layer.
• one, two, three, four or more than four intermediate layers are applied. In another embodiment, no intermediate layer is applied.
• the intermediate layers serve, inter alia, to control the diffusion or alloying process and can be used for targeted modification of the layer structure, the layer composition and thus the layer properties and the properties of the interdiffusion zone between substrate and alloyed functional layer.
• the layer composition can be set largely or completely substrate-independent.
• the interlayers may further prevent the formation of Kirkendall pores and may complicate, prevent or even improve interdiffusion between the substrate and the outer layer.
• the at least one metallic layer applied by means of a spraying process conforming to the contour or by means of shape-deposition-manufacturing is the outer layer.
• all layers are applied by means of a spraying process.
• At least one of the applied layers preferably an intermediate layer, via a continuous or discontinuous chemical or galvanic process, via a physical vapor deposition (PVD), by means of ionic liquids or by organometallic vapor deposition ( English metal organic chemical vapor deposition, MOCVD) deposited.
• PVD physical vapor deposition
• MOCVD organometallic vapor deposition
• Ionic liquids are non-volatile salts with a melting point below 100 ° C.
• suitable ionic liquids are preferably selected from the group consisting of trihexyl (tetradecyl) phosphonium chloride ((C6) 3 (C14) PCl), 1-octadecyl-3-methylimidazolium chloride ((C18) MIMCl), benzyltriethylammonium (C13H22NCl ), 1-heptyl-3-methylimidazolium chloride ((C7) MIMCl), 1-hexyl-3-methylimidazolium chloride ((C6) MIMCl), 1-butyl-3-methylimidazolium chloride (BMIMCl) and 1-ethyl-3-methylimidazolium chloride (EMIMCl ).
• the PVD process results in hard functional layers, where typically the very thin ceramic coatings are applied directly to the substrate.
• the optional production of the hard functional layers is separated from the application of the further metallic layers, so that these hard functional layers are formed by diffusion from the available elements only in the subsequent heat treatment.
• This offers over the pure PVD method the further advantage that in the process of the invention during the subsequent heat treatment by interdiffusion, on the one hand, the formation of the functional layers and on the other the formation of a diffusion zone below the functional layers is carried out, anchoring on the substrate took place Has. This has the consequence that must not be expected in the process according to the invention with Delaminationserscheinitchitch the hard functional layers.
• the MOCVD process is a CVD process (chemical vapor deposition) based on volatile organic compounds.
• Volatile metal compounds are understood to mean those which have a sublimation or boiling point of 300 ° C. or less at normal pressure (101.325 kPa).
• Suitable metal compounds are selected from the group consisting of metal-alkylene, preferably C 1 -C 10 -alkyl, metal-carbonyl, metal- ⁇ -complexes and metal compounds having several of these structures mixed. Particularly preferred are triethylaluminum (TEAL), triisobutylaluminum (TIBAL), diisobutylaluminum hydride (DIBAL), chromium hexacarbonyl and nickel tetracarbonyl.
• TEAL triethylaluminum
• TIBAL triisobutylaluminum
• DIBAL diisobutylaluminum hydride
• particle sizes of the coating material of 10 to 50 ⁇ m are preferably used.
• layer thicknesses of 0.02 to 5 mm can be achieved.
• Deposition (a) of the metal layers preferably takes place above all during cold spraying in a temperature range in which diffusion processes do not yet take place at a measurable speed. This results in that the interdiffusion, ie the diffusion of the elements of the individual layers between the layers, is omitted and the diffusion step is adjusted as an independent, diffusion heat treatment (b) in a separate process step.
• the separation of the deposition (a) of the metal layers from the diffusion step i. H. the successive application of coating and diffusion heat treatment (b), makes it possible to adapt the diffusion layer completely to the requirements of the diffusion process and the possible requirements of a heat treatment of the substrate or a further surface and / or substrate modification by process gases or other media, without the procedural restrictions To have consideration.
• the substrate according to the invention is preferably electrically conductive, particularly preferably selected from the group consisting of metallic substrates and / or metallized substrates.
• the subsequent diffusion heat treatment (b) is in a particular embodiment at a temperature of 250 ° C to 1600 ° C, preferably at 500 ° C to 1400 ° C, preferably at a temperature of 800 ° C to 1300 ° C, more preferably in a Temperature of 900 ° C to 1200 ° C performed.
• steps (a) and (b) are repeated one after another.
• the diffusion heat treatment (b) is carried out in a multi-stage temperature-time regime in the range of 400 to 1100 ° C.
• the diffusion heat treatment can be performed so that the structure of the substrate is selectively changed, for example by austenitizing.
• the diffusion heat treatment (b) is preferably carried out for a period of 3 hours or more to 250 hours, preferably 4 hours or more to 16 hours, more preferably 5 hours or more to 12 hours.
• the subsequent diffusion heat treatment (b) is carried out in an open oven and / or in a vacuum (eg in an induction oven) and / or in the presence of process gases and / or other media.
• process gases in the process according to the invention are argon, hydrogen, nitrogen, nitrogen-containing gases, carbon-containing gases, boron-containing gases and mixtures thereof.
• the carbon-containing gas is preferably methane, ethane, propane, butane, acetylene, carbon monoxide or a mixture thereof.
• the diffusion layer obtained by the method according to the invention is characterized in that it contains carbides and / or nitrides and / or carbonitrides and / or borides.
• carbon may also migrate to the forming diffusion layer to form metal carbides.
• organic radicals or oxygen can be removed.
• the subsequent diffusion heat treatment is carried out in the presence of a process gas and / or an accelerated cooling / quenching in the presence of process gases, as mentioned above, and / or other media is carried out in a further step (c).
• process gases and / or other media are preferably used.
• Controlled, preferably accelerated cooling of the coated substrate may also be carried out in the presence of liquid media such as oil, water, salt baths, liquid gases or molten lead.
• the substrate in particular the metallic substrate or the metallization of the substrate of unalloyed, low or high alloy steel, cast iron, cast steel, pure Cu, a Cu-based alloy, pure Ni, a Ni or Co base alloy, pure Ti, a Ti alloy or ⁇ -TiAl, the metals W, Mo, Ta, Nb, Zr, V, Hf, Ru, Rh, Os, Ir, Pd, Pt, Re or alloys, which is a main constituent of one of the elements W , Mo, Ta, Nb, Zr, V, Hf, Ru, Rh, Os, Ir, Pd, Pt, Re.
• iron-based materials such as unalloyed, low-alloyed or high-alloyed steel, cast iron, cast steel, and / or nickel-based materials, such as pure Ni or Ni base alloys, are preferred as the substrate.
• the at least one deposited metallic layer preferably consists of pure Al, Ti, Si, Y, Hf, Ni, Co, Mn, Cr, W, Mo, Pt, Pd, Ir, Rh, Re, Au, Ag, Cu, Ta or a single- or multi-phase alloy or mixture of these metals as the main constituent, which optionally additionally contains P and / or B and / or N and / or C.
• the at least one layer consists of more than one element, whereby a relatively shorter time for the diffusion heat treatment is required because of the intimate mixing of the elements within the applied layer than if the same elements were applied successively in different layers.
• the outer layer consists of Al, Ti, Si, Y, Hf, Ni, Co, Mn, Cr, W, Mo, Pt, Pd, Ir, Rh, Re, Au, Ag, Cu or mixtures and optionally additionally P and / or B and / or N and / or C.
• the outer layer consists of a material selected from the group consisting of pure Al, AlNi alloys, Cr, AlCr alloy, TiAl Alloy, NiAlTi alloy.
• the intermediate layer (s), if present, preferably consist of pure Ni, Co, Mn, Cr, W, Mo, Pt, Pd, Ir, Rh, Re, Au, Ag, Cu or a single- or multiphase alloy, which contains as the main constituent of one of the elements Ni, Co, Mn, Cr, W, Mo, Pt, Pd, Ir, Rh, Re, Au, Ag, Cu and optionally additionally P and / or B and / or N and / or C.
• the last applied intermediate layer of nickel, d. H. the outer layer is applied directly to a Ni layer.
• none of the layers applied contain element combinations selected from the group consisting of NiCr, NiCrB, NiCrBSi, NiCrP, FeCrC, FeCrB and mixtures thereof, alone or in admixture with WC.
• the elements nickel and / or chromium and / or phosphorus and / or boron and / or silicon and / or copper and / or iron and / or tungsten are not included in any of the applied layers.
• the applied layer is not made of solder.
• mixed layers of NiAl and / or NiAlCr and / or AlCr and / or TiAl and / or NiAlTi or pure aluminum or pure chromium layers are preferably applied to the substrate, wherein the substrate is preferably coated with a nickel layer.
• the diffusion layer formed according to the invention contains, in addition to the elements of the outer layer as alloy constituents, at least one element of, if present, at least one intermediate layer and optionally of the substrate metal.
• the preferred layer thickness of an intermediate layer and / or the outer layer is 0.1 ⁇ m to 2 mm, preferably from 1 ⁇ m to 100 ⁇ m, particularly preferably from 2 ⁇ m to 50 ⁇ m. In one embodiment, the layer thickness of the outer layer and the intermediate layers is variable per 10-500 microns.
• the diffusion layer formed according to the invention preferably has a layer thickness of from 0.2 ⁇ m to 4 mm, preferably from 2 ⁇ m to 800 ⁇ m, particularly preferably from 4 ⁇ m to 250 ⁇ m.
• substrates with complex topographies can be coated accurately and precisely.
• a conformal coating of the substrate takes place.
• dog bone effect excessive layer structure, especially in the edge / corner area, which occurs in particular in galvanic coatings, is avoided.
• the method according to the invention is likewise suitable for coating large-area substrates which are required, for example, for industrial installations.
• the respectively required surface properties of the material to be produced are arbitrarily adjustable. Kirkendall pore spaces, on the other hand, can be largely avoided.
• Materials produced by the method according to the invention are characterized by the absence of cracking and / or Kirkendall pores.
• the method according to the invention makes it possible to set the desired structure state by means of targeted temperature control during the process, e.g. Austenitizing.
• the material according to the invention is preferably used as oxidation protection, scale protection, hot gas corrosion protection, protection against metal dusting, protection against sulfidation, corrosion protection, wear protection, increase of the abrasive resistance, reduction of adhesion, improvement of tribological properties and / or Protection against aggressive molten metals used.
• Products comprising the material of the invention include semi-finished products, workpieces, moldings and components.
• Products according to the invention are preferably used in general mechanical engineering, the construction and vehicle industry, in aviation, z. B. in sealing systems or as oxidation-resistant rubbing seal in the exhaust of automotive application, z. As a heat shield, in the petrochemical industry as well as in the chemical and general industry.
• bearings as well as tools for cold and hot work, in particular casting tools, mold punches, forming tools, wires, sheets, screws, nuts, machine components, engines, engines or parts thereof z.
• a material St37 is applied by cold spraying a Ni-Al layer structure.
• the subsequent heat treatment in the temperature range of 600-1000 ° C for 5 to 8 hours, a NiAl diffusion layer is produced on the surface.
• the surface preferably forms the ⁇ -NiAl phase known from aviation.
• the Ni-rich layer which remains over the substrate, the stability of the layer structure is ensured by thermal aging and also prevents the formation of Kirkendall pores.
• a material St37 is applied by cold spraying a Ni-Al layer structure.
• the subsequent heat treatment in the temperature range of 600-1000 ° C for 2 to 5 hours, a NiAl diffusion layer is produced on the surface.
• the treatment time is shorter than in Example 1, since only an anchoring of the Ni and NiAl layer on the substrate and each other must be done.
• the surface preferably forms the ⁇ -NiAl phase known from aviation.
• the Ni-rich layer which remains over the substrate, the stability of the layer structure is ensured by thermal aging and also prevents the formation of Kirkendall pores.
• a 50 ⁇ m thick chromium layer was applied in the cold gas spraying process.
• a subsequent 8 to 12 hours lasting Heat treatment at 900 to 1150 ° C under nitrogen and oxygen-free argon as a protective gas which here additionally enables hardening of the substrate by targeted austenitizing and subsequent rapid cooling by blowing argon, forms a chromium-carbide alloy layer on the surface which in particular has the composition Cr23C6.
• the carbon passes from the steel by diffusion through the intermediate layer into the outer chromium layer, where it forms chromium carbide.
• this structure In addition to the very hard edge zone of about 2000 HV 0.01 (Vickers hardness), this structure has a substrate that is relatively soft with about 200HV, which, in addition to a strong anticorrosion effect, enables the reduction of stresses. The result is therefore a crack-free structure of the very hard outer Cr carbide layer in contrast to the previously known Inchromier Anlagenen without nickel intermediate layer, which show clearly normal cracks to the surface.
• a material St37 is applied by cold spraying a Ni-AlCr layer structure and subsequently subjected to a heat treatment in the temperature range of 600-1150 ° C for 2 to 5 hours.
• a ternary alloy structure of Al, Cr and Ni is formed on the surface.
• These Al-Cr-Ni layer structures are known from the aerospace industry and are not used there because of very complicated co-deposition of aluminum and chromium via packing or CVD process.
• the nickel-rich layer which remains above the substrate, ensures the stability of the layer structure during thermal aging and also avoids the formation of Kirkendall pores.
• a material St37 is applied by cold spraying a Ni-TiAl layer structure and subsequently subjected to a heat treatment in the temperature range of 600-1150 ° C for 2 to 5 hours.
• a ternary alloy structure of Ti, Al and Ni forms on the surface. Due to their Ti content, these Ti-Al-Ni layer structures are considered to be very stable in sulfiding environments. By the Ni-rich layer, which is above the substrate remains, the stability of the layer structure is ensured by thermal aging and also the formation of Kirkendall pores is avoided.
• a Ni-NiTiAl layer structure is applied to a material St37 by cold spraying and subsequently subjected to a heat treatment in the temperature range of 600-1150 ° C. for 2 to 5 hours.
• the treatment time is shorter than in example 5, since only the anchoring of the Ni and NiTiAl layer on the substrate and each other must be carried out.
• a ternary alloy structure of Ti, Al and Ni forms on the surface. Due to their Ti content, these Ti-Al-Ni layer structures are considered to be very stable in sulfiding environments.
• the Ni-rich layer which remains above the substrate, ensures the stability of the layer structure upon thermal aging and also avoids the formation of Kirkendall pores.
• a more than 50 micron thick Ni layer was sprayed by means of Shape Deposting Manufacturing (SDM) computer-assisted and then computer-aided by milling , Turning and polishing processes brought to 50 microns Gauge. Then a more than 50 microns thick Cr layer was sprayed by means of SDM method and then brought back to final size as described above. Subsequent heat treatment for 7 hours at 750 ° to 1250 ° C.
• SDM Shape Deposting Manufacturing
• a Ni layer and then an AlCr mixed layer is applied by means of cold spraying method first, d. H. an aluminum matrix in which chromium is embedded. Subsequently, the coated substrate was subjected to a heat treatment in the temperature range of 600-1200 ° C for 10 to 15 hours.
• a Ni layer is first applied by electroplating. Subsequently, in a first packing step in the temperature range of 900 ° C - 1200 ° C, a chromium layer, then in a second packing step at a temperature of 600 ° C - 1200 ° C applied an Al layer. A heat treatment is carried out simultaneously with the application of the Cr and Al layers over 10 to 15 hours.
• Example 8 Comparative example substratum ferrite ferrite layer structure Ni CrAl (cold gas spraying) Ni (galvanic) Cr (1st packing step) Al (2nd packing step) heat treatment Downstream 10 - 15 hours At the same time with Cr and Al application 10 - 15 hours Multilayer structure from outside to inside CrAl (Ni) NiAl NiFe substrate CrAl CrC NiCr (Fe) Substrate Properties of the produced material continuous hardness profile, the hardness drops towards the substrate very hard CrC intermediate layer with 2000HV hardness, which leads to high hardness cracks in the coating, these can have a negative effect on adhesion and wear resistance very good oxidation resistance and sulfidation resistance

Priority Applications (1)

Applications Claiming Priority (1)

Publications (1)

Family

ID=38567060

Family Applications (1)

Country Status (1)

Cited By (14)

Citations (16)

• 2007
  • 2007-05-25 EP EP07109007A patent/EP1995344A1/fr not_active Withdrawn

Patent Citations (16)

Similar Documents

Legal Events