Abstract:
Thermal spray processing and cold spray processing are utilized to manufacture porous starting materials (such as tube stock, wire and substrate sheets) from biocompatible metals, metal alloys, ceramics and polymers that may be further processed into porous medical devices, such as stents. The spray processes are also used to form porous coatings on consolidated biocompatible medical devices. The porous substrates and coatings may be used as a reservoir to hold a drug or therapeutic agent for elution in the body. The spray-formed porous substrates and coatings may be functionally graded to allow direct control of drug elution without an additional polymer topcoat. The spray processes are also used to apply the drug or agent to the porous substrate or coating when drug or agent is robust enough to withstand the temperatures and velocities of the spray process with minimal degradation.
Abstract:
A method of supplying a coating to a substrate by spraying heated particles of a coating material onto the substrate. The particles are heated to a temperature and sprayed at a velocity such that the total energy of the particles is less than the energy necessary to melt the particles. When the particles collide with the substrate the particles may plastically deform to a diameter with the substrate that is greater than the diameter of the particle prior to colliding with the substrate. The deformed particle may bond to the substrate about the majority of the deformed diameter of the particle.
Abstract:
A combustion apparatus is provided having a pre-combustion chamber and a combustion chamber. The pre-combustion chamber houses a preheating combustion for preheating and at least partially vaporizing fuel supplied to the pre-combustion chamber. The preheating combustion is controlled so that only a portion of the fuel supplied to the pre-combustion chamber is burned. The combustion apparatus further include a primary combustion oxidizer supply located downstream of said preheating combustion. The primary combustion oxidizer supply supplies an amount of oxidizer to allow the fuel not burned by the preheating combustion to burn.
Abstract:
The invention relates to devices for the treatment of heart disease and particularly to endo-arterial prostheses, which are commonly called stents. More particularly, the invention relates to methods of manufacturing and coating stents utilizing thermal spray processing (TSP). In one aspect the invention involves the use of TSP for the manufacture of fine grained tubing for subsequent use as a stent or other tubular or ring-based implant, or the manufacture of intermediate sized tubing that may then be drawn to final size tubing and for the coating of a stent. An average grain size of less than 64 microns is achieved by the invention resulting in a stent having an annular wall average thickness of about eight or more grains.
Abstract:
The invention relates to devices for the treatment of heart disease and particularly to endo-arterial prostheses, which are commonly called stents. More particularly, the invention relates to methods of manufacturing and coating stents utilizing thermal spray processing (TSP). In one aspect the invention involves the use of TSP for the manufacture of fine grained tubing for subsequent use as a stent or other tubular or ring-based implant, or the manufacture of intermediate sized tubing that may then be drawn to final size tubing and for the coating of a stent. An average grain size of less than 64 microns is achieved by the invention resulting in a stent having an annular wall average thickness of about eight or more grains.
Abstract:
The invention relates to a powder supply system (1) for supplying a processing apparatus (2) with a granular substance (3). In this arrangement the powder supply system (1) includes a main container (4) and a powder conveying system (5) with a storage container (51) for conveying the granular substance (3) into the processing apparatus (2). In accordance with the invention means (6, 611, 612, 62) are provided so that, in the operating state of the processing apparatus (2), a predetermined amount of the granular substance (3) can be conveyed from the main container (4) as working powder to the storage container (51) in such a way that at least a minimum amount (M1) is available as a granular substance (3) in the storage container (51).
Abstract:
Disclosed is a system and a method for applying both a kinetic spray applied coating layer and a thermal spray applied layer onto a substrate using a single application nozzle. The system includes a higher heat capacity gas heater to permit oscillation between a kinetic spray mode wherein the particles being applied are not thermally softened and a thermal spray mode wherein the particles being applied are thermally softened prior to application. The system increases the versatility of the spray nozzle and addresses several problems inherent in kinetic spray applied coatings.
Abstract:
A deposit is formed on a deposition substrate using a deposition gun that burns a mixture of a fuel and an oxidizer to form a deposition gas flow, mixes a powder into the deposition gas flow to form a deposition mixture flow, and projects the deposition mixture flow therefrom. The deposition gun is provided with a flowing coolant. A flow rate of the fuel to the deposition gun, a flow rate of the oxidizer to the deposition gun, a flow rate of the powder to the deposition gun, and a cooling capacity of the coolant flow are all measured. The flow rate of the fuel, the flow rate of the oxidizer, the flow rate of the powder, and the cooling capacity of the coolant flow are all controlled responsive to the step of measurements.
Abstract:
A high velocity thermal spray gun includes a nozzle member injecting an annular flow of combustible mixture at high pressure into a constricted gas cap. An outer flow of air is injected adjacent to the gas cap wall. Powder is fed axially from the nozzle member into the combustion chamber. An annular inner flow of air is injected coaxially outwardly of the powder. The nozzle face has a shallow annular slot therein between the outer and inner gas injections. Combustion gas and oxygen flow through separate annular gas channels to mutually impinge at the inlet end of the slot for effectual mixing, so that combusting of the combustible mixture is rooted in the annular slot.
Abstract:
A flame spray directing means for connection to a flame spray nozzle of an autogenous flame-spraying apparatus for optimizing the working parameters of the apparatus including flame speed and kinetic energy is provided. The means comprises a hollow longitudinally extending module of tubular configuration through which flame spray material is caused to flow. The extending module has a predetermined length with one end portion thereof shaped for coupling to the flame spray nozzle and for providing a combustion chamber therefor, with its opposite end portion providing an exit end therefor. A portion of the hollow module extending from the combustion chamber to the exit end coaxially defines an extending accelerating chamber which is divided into a first stage chamber of specified diameter following the combustion chamber and a second stage chamber in which the diameter thereof less than that of the combustion chamber.