Abstract: A method of forming a hollow structure in an additively manufactured object involves creating a pattern on a surface of a base material of the object with a sacrificial metal filler having a melting point of 350° C. or less, the pattern defining a shape of the hollow structure on the base material. A metal layering material is cold sprayed over the sacrificial metal filler and at least a portion of the base material. The sacrificial metal filler is removed from the pattern by melting the sacrificial metal filler without melting or deforming the base material or the metal layering material to leave the hollow structure in the object formed from the pattern. Non-standard cold spray conditions are used with the metal layering material to prevent damage and or displacement of the filler while still forming a coating of the metal layering material on the filler and base material.

Abstract: A technique for improving cold spray deposition conditions for cold spray additive manufacture of parts involves providing an in-situ temperature feedback controller with a remote instantaneous temperature sensor supplying surface temperature measurements of the deposition surface, and a (preferably long pulse) laser for heating. Temperature feedback allows for control over deposition conditions yielding predictable deposition properties.

Abstract: A technique for joining parts of incompatible metals involves cold spraying a 150-900 micron thick layer of a metal compatible with the second part onto the first part, and friction stir joining the parts by lap welding while keeping a tool of the FSJ tool at least 300 microns away from the first part (less layer) throughout the joining, to avoid damaging the cold spray to first part interface, and formation of intermetallics. Fatigue resistance was tested, with and without a sealant.

Abstract: A method of forming a hollow structure in an additively manufactured object involves creating a pattern on a surface of a base material of the object with a sacrificial metal filler having a melting point of 350° C. or less, the pattern defining a shape of the hollow structure on the base material. A metal layering material is cold sprayed over the sacrificial metal filler and at least a portion of the base material. The sacrificial metal filler is removed from the pattern by melting the sacrificial metal filler without melting or deforming the base material or the metal layering material to leave the hollow structure in the object formed from the pattern. Non-standard cold spray conditions are used with the metal layering material to prevent damage and or displacement of the filler while still forming a coating of the metal layering material on the filler and base material.

Abstract: A technique for joining parts of incompatible metals involves cold spraying a 150-900 micron thick layer of a metal compatible with the second part onto the first part, and friction stir joining the parts by lap welding while keeping a tool of the FSJ tool at least 300 microns away from the first part (less layer) throughout the joining, to avoid damaging the cold spray to first part interface, and formation of intermetallics. Improved fatigue resistance is shown. A sealant can advantageously further improve fatigue resistance.

Abstract: A method for applying a coating to a substrate surface is provided. The method involves cold spraying a coating material against the surface of the substrate at a first velocity. The first velocity is lower in magnitude than a critical velocity. The method also involves cold spraying the coating material against the surface of the substrate at a second velocity. The second velocity is greater in magnitude than the critical velocity. The critical velocity is a threshold velocity below which the coating material is substantially deflected by the surface of the substrate and above which the coating material substantially adheres to the surface of the substrate.

Abstract: A wear resistant friction coating (WRFC) can be applied on a lightweight metallic substrate, by applying a cold gas dynamic spray bond coat containing more iron than any other single element directly onto a surface of the substrate, and thermal spraying the WRFC coating over the bond coat to a thickness of at least 500 ?m. Corrosion resistance, adhesion, thermal cycling resistance, and wear resistance have been demonstrated.

Abstract: A powder fluidizing system, comprising a pressure vessel, a powder container removably mounted within the pressure vessel, and comprising a bottom sieve; a vibrator generating vibrations and transmitting the vibrations to the powder container above the sieve; and a guide directly secured under said powder container to the bottom sieve; wherein a bulk powder fed within the powder container is vibrated within the powder container and flows through the sieve to the guide, and a powder fluidizing method, comprising feeding a bulk powder within a powder reservoir maintained under pressure; vibrating the powder reservoir; and passing the powder through a sieve positioned at the bottom of the powder reservoir.

Abstract: A method for applying a coating to a substrate surface is provided. The method involves cold spraying a coating material against the surface of the substrate at a first velocity. The first velocity is lower in magnitude than a critical velocity. The method also involves cold spraying the coating material against the surface of the substrate at a second velocity. The second velocity is greater in magnitude than the critical velocity. The critical velocity is a threshold velocity below which the coating material is substantially deflected by the surface of the substrate and above which the coating material substantially adheres to the surface of the substrate.

Abstract: A method for applying a coating to a substrate surface is provided. The method involves cold spraying a coating material against the surface of the substrate at a first velocity. The first velocity is lower in magnitude than a critical velocity. The method also involves cold spraying the coating material against the surface of the substrate at a second velocity. The second velocity is greater in magnitude than the critical velocity. The critical velocity is a threshold velocity below which the coating material is substantially deflected by the surface of the substrate and above which the coating material substantially adheres to the surface of the substrate.

Abstract: A powder fluidizing system, comprising a pressure vessel, a powder container removably mounted within the pressure vessel, and comprising a bottom sieve; a vibrator generating vibrations and transmitting the vibrations to the powder container above the sieve; and a guide directly secured under said powder container to the bottom sieve; wherein a bulk powder fed within the powder container is vibrated within the powder container and flows through the sieve to the guide, and a powder fluidizing method, comprising feeding a bulk powder within a powder reservoir maintained under pressure; vibrating the powder reservoir; and passing the powder through a sieve positioned at the bottom of the powder reservoir.

Abstract: A method and apparatus by which liquid feedstock suspensions containing fine particles, micron- and nano-sized, are injected, with sufficient droplet velocity, preferably axially, into a plume of a thermal spray apparatus for the production of high-quality nanostructured coatings allows complete entrainment of the droplets in the plume, while the injection orifice remains potentially blockage-free for long periods of operation. The method and apparatus permit delivery at a low flow rate and with sufficient velocity to permit effective deposition, while reducing obstructions for a suspension feedstock delivery system and permits suspension feedstock to be controlled and delivered with reduced sensitivity of the spray process on the injection conditions to enable production of nanostructured coatings.

Abstract: A method of coating a surface of a substrate with a particulate coating material, the method comprising: determining at least an area of the surface of the substrate to be covered with the particulate coating material; subjecting at least a portion of the area of the surface of the substrate to laser irradiation to form a plurality of distinct spaced-apart laser impact craters in a pattern and/or at least one last impact pit on the surface of the substrate; and thermally spraying the area of the surface of the substrate with the particulate coating material. A coated substrate comprising: a substrate having a plurality of distinct spaced-apart laser impact craters in a pattern and/or at least one laser impact pit on at least an area of a surface of the substrate; a thermally-sprayed coating mechanically bonded to at least the area of the surface of the substrate.

Abstract: A method for producing nanostructured coatings on a substrate, comprising: preparing a nanocrystalline powder of a powder size comprised between 1 and 60 ?m; and combining cleaning the surface of the substrate and cold spraying the nanocrystalline powder on the surface of the substrate, and a system for producing nanocrystalline coatings on a substrate, comprising a spray head, a cleaning head and a handling system monitoring the spray head and the cleaning head relative to the substrate to be coated, the spray head being a first cold spray head, the first cold spray head depositing on the substrate at least one nanocrystalline powder, the cleaning head optimizing the surface being coated with the at least one layer of nanocrystalline powder.

Abstract: A method for producing nanostructured coatings on a substrate, comprising: preparing a nanocrystalline powder of a powder size comprised between 1 and 60 ?m; and combining cleaning the surface of the substrate and cold spraying the nanocrystalline powder on the surface of the substrate, and a system for producing nanocrystalline coatings on a substrate, comprising a spray head, a cleaning head and a handling system monitoring the spray head and the cleaning head relative to the substrate to be coated, the spray head being a first cold spray head, the first cold spray head depositing on the substrate at least one nanocrystalline powder, the cleaning head optimizing the surface being coated with the at least one layer of nanocrystalline powder.

Abstract: It has been surprisingly found that injecting ceria-based particles (mean size less than 200 nm) suspended in a combustible organic solvent into a plume having a maximum temperature between about 2,600° C. and 4,000° C. to impart a mean temperature to the particles from about 2,600° C. to about 3,800° C., and to accelerate the particles to a mean velocity between about 600 to 1000 m/s, produces a thin, uniform, dense, crack-free, nanocrystalline ceria-based coating, which may be applied on porous cermet or metal substrate, for example. The physical environment of a high-velocity oxy-fuel (HVOF) thermal spraying gun suitably ably deployed using standard fuels produces these conditions. The method of the present invention is particularly useful for the cost-effective fabrication of ceria-containing electrolytes for solid oxide fuel cells (SOFCs).

Abstract: Bone tissue at the interface of a bone implant is shielded from stresses found in normal bone because of the higher stiffness or rigidity in the implant versus in bone. The resulting “stress shielding” of the bone by the implant eventually results in resorption of bone at the bone-implant interface and ultimately necessitates replacement of the bone implant. To overcome these problems, an implantable biomimetic prosthetic bone having a porous surface, a fiber-reinforced composite structure, and a polymer-based core is disclosed. The prosthetic bone is a good match for structure, stiffness, viscoelastic properties, specific weight and overall structure as real bone or host tissues adjacent to the prosthetic bone. The prosthetic bone may be formed as a total hip prosthesis.

Abstract: A tie layer for bonding a ceramic or metallic coating to a thermoplastic substrate is described. The tie layer comprises from 2 to 70% ceramic and/or metallic filler particles in a thermoplastic matrix. The thermoplastic matrix is compatible with the thermoplastic substrate. Further, a method of bonding a ceramic or metallic coating to a thermoplastic substrate is disclosed. The method involves applying the tie layer to the substrate, and bonding the ceramic or metallic coating to the tie layer using a coating process that consolidates the substrate, the tie layer and the coating. The tie layer and process are useful in coating implantable prosthetic bones, or coating industrial items used in automotive, aeronautical or medical industries.

Abstract: A method and product derived therefrom for consolidating nanoparticles to form particles in a micrometric size distribution. The method preserves the nanoparticles with the resultant micrometric particles. The primary processing operation is milling.

Abstract: This invention relates to a method by which liquid feedstock suspensions containing fine particles, micron- and nano-sized, are injected, with sufficient droplet velocity, preferably axially, into a thermal spray apparatus for the production of high-quality nanostructured coatings. The method allows complete entrainment of the droplets in a high temperature gas stream, while the injection orifice remains potentially blockage-free for long periods of operation.