Abstract: A manufacturing method of an auger composed of an auger body integrally formed thereon with a spiral blade and at its opposite ends with a pair of shaft portions, comprising the steps of forming annular recesses on the shaft portions respectively in a cutting process, building up an anti-abrasive and anti-corrosive alloy by plasma-arc welding in the annular recesses of the shaft portions and finishing each built-up portion of the alloy in a grinding process to form a journal portion on the respective shaft portions of the auger, wherein precipitation hardening stainless steel used as a base metal of the auger body is preheated for a predetermined time prior to the plasma-arc welding of the alloy and subjected to aging heat treatment caused by the preheating and welding heat during the plasma-arc welding process for precipitation hardening.

Abstract: A torch head includes a torch body which is inserted into the tube member, a cathode tube which is arranged in the torch body such that the longitudinal axis of the cathode tube is aligned to the longitudinal axis of the torch body and which has a cathode at the distal end of the cathode tube, an anode member which is arranged on the distal end side of the cathode tube, and a spraying material supply tube which opens toward a mouth opening formed in the anode member and which is arranged outside the torch body. In the anode member, a plasma gas supply chamber in which the front end of the cathode tube is stored in a non-contact state, an orifice which communicates with the plasma gas supply chamber and in which the cathode is stored in a non-contact state, and a plasma generation chamber which communicates with the orifice, which has a longitudinal axis substantially perpendicular to the longitudinal axis of the torch body, and which has the mouth opening are formed.

Abstract: A method of producing nanocrystalline ceramic powder by creating a plasma stream in a reactor vessel, and physically converting a ceramic precursor material into ceramic particles suspended in the vessel, using the plasma stream. A metallic reactant may additionally be introduced into the vessel using the plasma stream, wherein the metallic reactant forms ceramic particles having the same composition as the ceramic particles of the physical converting step. The plasma stream is created using an electrothermal gun. The gun may use a ceramic barrel which is eroded by the plasma stream. Alternatively (or additionally), the ceramic precursor material may be injected as particulates into the plasma stream, wherein the ceramic precursor particulates are micron-sized or larger. A novel electrothermal gun design may optionally use a replaceable insert constructed of the ceramic precursor material.

Abstract: The invention recites a plasma-arc spray gun comprising a cathode and an anode defining a longitudinal axis. The anode further includes an external surface and an internal chamber, the internal chamber extending from a first end to a second end. At least a portion of the internal chamber is defined by revolving a non-linear curve about the longitudinal axis. The plasma-arc spray gun also includes a gun body supporting the cathode and the anode.

Abstract: The multi-layered heat resistant metal tube is disclosed. This tube has excellent anti-coking characteristics and is suitable for use under the conditions where carbon tends to deposit and accumulate thereon due to contacting with hydrocarbons at a high temperature. The tube is made by forming weld-mounted overlaid layer of Cr—Ni alloy by building-up welding over the inner surface and/or the outer surface of a substrate tube made of a heat resistant metal. The Cr—Ni alloy comprises 35% by weight or more of Cr and satisfies the relationship: Ni(w%)≧0.5Cr(wt %). Building-up welding is preferably carried out by PPW (Plasma Powder Welding) in which the filler metal is supplied in the form of powder.

Abstract: A system for fine feature spray deposition includes a substrate platform for supporting a substrate on which the features are to be deposited. A spray assembly is provided which includes a spray source for providing a stream of material to be deposited on a substrate, a collimator which is positioned in a path of the stream from said spray source and an aperture assembly, which is positioned downstream of the collimator with respect to the spray source and above the substrate platform. The aperture assembly defines at least one opening to pass a portion of the stream of material onto a surface of the substrate. A drive mechanism is provided which is coupled to at least one of the spray assembly and the substrate platform for inducing relative motion there between. A controller is coupled to the spray assembly and the drive mechanism to control the relative motion and the stream of material. The system allows fine features to be printed directly on a substrate with requiring a predefined mask.

Abstract: A method and system for producing a transparent, electrically conductive coating onto a substrate. The method includes: (a) operating a twin-wire arc nozzle to heat and at least partially vaporize two wires of a metal composition for providing a stream of nanometer-sized vapor clusters of the metal composition into a chamber in which the substrate is disposed; (b) introducing a stream of oxygen-containing gas into the chamber to impinge upon the stream of metal vapor clusters and exothermically react therewith to produce substantially nanometer-sized metal oxide clusters; and (c) directing the metal oxide clusters to deposit onto the substrate for forming the coating.

Abstract: A cathode assembly 10 for an electric arc spray apparatus. The cathode assembly 10 utilizes a positive cathode retention design which provides for improved heat management characteristics, quick and easy cathode replacement and increased cathode life. The cathode assembly includes a cathode holder 14, a cathode 12 including a first portion 26 which resides within the cathode holder 14, a tip portion 28 which extends from the cathode holder, and a shoulder portion 33 which is formed on the outer surface of the cathode. The cathode assembly 10 further includes a retention member or nut 16 which removably attaches to the cathode holder 14 and which engages the shoulder portion 33, effective to positively retain the cathode 12 within the holder 14. The retention member 14 also includes an aperture through which the cathode tip 28 extends.

Abstract: A method for closing and/or joining a connecting joint or joining seam between two pieces of galvanized sheet metal, in which zinc or a zinc alloy whose melting point is similar to that of zinc is heated to melting temperature and is continuously introduced into the connecting joint, with the heating being performed by a plasma jet without reaching the melting temperature of the steel sheet. The use of a plasma jet allows processing zinc or, a zinc alloy without producing any disturbing zinc spatter. The zinc can be supplied as a wire, powder or granulate, whereby it is introduced under an inert-gas bell. This method can also be employed for post-galvanizing weld seams, with a second plasma jet welding set following a first one, it being mechanically coupled with the same and performing the galvanizing of the weld seam by the supply of zinc in wire form without melting the steel sheet anew. Tin foils are used in a special embodiment which are applied in the joining zone of a flanged edge.

Abstract: In a system based on aluminum, zirconium and nitrogen at least one layer has covalent bonds of aluminum nitride or at least one layer has bonds of the aluminum nitride and zirconium nitride type. In a process for producing such a system an electrical gas discharge is fired in a vacuum chamber such as essentially to form a noble gas-enriched plasma resulting in ionization of the metal elements. To form the nitridic layer nitrogen is continuously fed as a reactive gas into the vacuum chamber and pumped away so as to set a reactive gas partial pressure which is used for process control purposes. The use of such a system for producing a coating on a surface is also described.

Abstract: A system and method for depositing a CVD diamond coating on a non-planar surface of an object is provided. The system includes a deflector having a deflecting surface which resists diamond coating by the diamond forming reagents produced by the system and which is adapted to withstand the relatively high deposition temperatures is provided. The deflector is positioned substantially axially with an axis of the distribution head of the CVD engine. The deflector is preferably generally wedge-shaped or conical and coupled to a motor which is adapted to rotate the deflector at a relatively high speed. A mandrel may be positioned about or to one side of the deflector. The deflector is oriented with respect to the distribution head and the mandrel such that a jet exiting the distribution head is deflected by the deflector onto a surface of an object positioned on the mandrel. The object surface may be non-planar.

Abstract: An ion fusion formation (IFF) system uses a plasma welding torch to create ions that heat feedstock for application at a deposition point. A plasma welding torch may use argon gas or the like in order to provide extremely hot ions that impact or collide with the feedstock in order to melt it and enabling application of the melted feedstock to a deposition point on a workpiece. By positioning the workpiece, wire feeder, and/or welding torch, parts, devices, or components can be built in almost any three-dimensional shape. Parts can be manufactured in a “just-in-time fashion” with high precision and predictable performance.

Abstract: A method for protecting high temperature stainless steel from coking and corrosion at elevated temperatures in corrosive environments, such as during ethylene production by pyrolysis of hydrocarbons or the reduction of oxide ores, by coating the stainless steel with a coating of MCrAlX in which M is nickel, cobalt, iron or a mixture thereof and X is yttrium, hafnium, zirconium, lanthanum or combination thereof deposited onto and metallurgically bonded to the stainless steel by plasma transferred arc deposition of atomized powder of MCrAlX. The coating has a thick, dense, continuous and smooth transition region providing an effective metallurgically bond of the coating with the stainless steel. The coating retains a relatively high aluminum content which permits generation of an adherent alumina layer on the surface, providing good resistance to high temperature oxidation together with good anti-coking and hot erosion resistance properties.

Abstract: A method of producing nanocrystalline ceramic powder by creating a plasma stream in a reactor vessel, and physically converting a ceramic precursor material into ceramic particles suspended in the vessel, using the plasma stream. A metallic reactant may additionally be introduced into the vessel using the plasma stream, wherein the metallic reactant forms ceramic particles having the same composition as the ceramic particles of the physical converting step. The plasma stream is created using an electrothermal gun. The gun may use a ceramic barrel which is eroded by the plasma stream. Alternatively (or additionally), the ceramic precursor material may be injected as particulates into the plasma stream, wherein the ceramic precursor particulates are micron-sized or larger. A novel electrothermal gun design may optionally use a replaceable insert constructed of the ceramic precursor material.

Abstract: The invention relates to an apparatus for coating a substrate with a plasma arc torch, and with such a plasma arc torch the powdery additive is to be heated, melted open and accelerated towards the surface with plasma gas generated in the plasma arc torch, and with an additional laser beam. In the plasma arc torch, an annular cathode is located or a plurality of individual cathodes are arranged about a longitudinal axis. Gas is supplied into a plasma space which is located between such an annular cathode or the plurality of cathodes, and such an annular anode. With the invention, coating is to be allowed to be formed with a higher speed and deposition rate, respectively, with respect to the conventional solution with the same and increased quality, respectively, and the directional independence for the formation of the coating is to be ensured.

Abstract: A cutting edge is formed by build-up welding on a die of a die assembly made of a base material of an aluminum/copper-based zinc alloy. The cutting edge comprises an underlying layer and an overlying layer. The underlying layer is made of a copper alloy that can be welded to both a zinc alloy and a nickel alloy, and the overlying layer is made of a nickel alloy. The cutting edge is of high machinability, high durability, and high hardness.

Abstract: An automated hardfacing system useful for hardfacing roller cones is disclosed. The automated system includes a robot with an arm, a positioner, and a controller which co-ordinates the alignment of the robot and the positioner. The robot holds a hardfacing torch and is capable of movement in three axes of movement. These axes are the x, y, and z axes of the Cartesian co-ordinate system. The positioner holds a roller cone and is capable of movement in at least two axes of movement. The movement includes tilting and rotation about a Cartesian axis. The hardfacing coating produced by the automated system has improved quality and consistency as compared to the one obtained by a manual process.

Abstract: A feedstock injector for connection to a source of heated gas comprises a first plurality of channels arranged symmetrically about a longitudinal axis, the channels leading from the upstream end to an intermediate region of the injector. A second plurality of channels, coaxial with the first plurality of channels and arranged symmetrically about the same longitudinal axis, extend from the outlet ends of the first plurality of channels towards the downstream end of the injector and converge at a convergence angle towards a common region of convergence located downstream on the longitudinal axis. Feedstock material is injected axially towards the common region of convergence.

Abstract: Method of thermally depositing metal at increased rates onto a target surface, comprising: establishing and operating a high velocity plasma transferred wire arc between a cathode and the free-end of a consumable wire electrode, the energy of such plasma and arc being sufficient to not only melt and atomize the free-end of the wire into metal particles, but also project the particles as a column onto the target surface at an enhanced deposition rate for continuous periods in excess of 50 hours; surrounding the plasma and arc with high velocity and high flow gas streams that converge beyond the intersection of the wire free-end with the plasma-arc to limit turbulence of the plasma-arc, avoid direct impingement with the wire and assist the projection of the particles to the target surface; and impinging a low velocity gas flow along the axis of the advancing wire to counteract any destabilizing fluid dynamic forces attempting to move melted particles back along the wire away from the wire free end.

Abstract: The multi-layered heat resistant metal tube is disclosed. This tube has excellent anti-coking characteristics and is suitable for use under the conditions where carbon tends to deposit and accumulate thereon due to contacting with hydrocarbons at a high temperature. The tube is made by forming weld-mounted overlaid layer of Cr—Ni alloy by building-up welding over the inner surface and/or the outer surface of a substrate tube made of a heat resistant metal. The Cr—Ni alloy comprises 35% by weight or more of Cr and satisfies the relationship: Ni(w%)≧0.5Cr(wt %). Building-up welding is preferably carried out by PPW (Plasma Powder Welding) in which the filler metal is supplied in the form of powder.

Abstract: A radial bearing and method for making the same are disclosed. Radial bearings are typically used control the direction of drilling in directional drilling operations. The cuttings flow across the surfaces of the bearings before being removed from the well. The cuttings will contain sand and other hard and/or corrosive substances that will erode the surfaces of the bearings and shorten their useful life. The bearing of this invention is provided with a wear resistant surface to inhibit such erosion. The bearing is made from a bearing blank to which is applied a first overlay of mild steel with dispersed cemented metal carbide pellets. The composition of the cemented metal carbide pellets is disclosed. The first overlay may be applied by any conventional technique. A second overlay of mild steel is applied to the first overlay utilizing a MIG welding process. As the second overlay is applied, a portion of the hard metal particles in the first overlay is dispersed in the weld puddle forming the second overlay.

Abstract: The present invention relates to a plasmatron for a plasma coating apparatus including an anode having an axial bore through which gas is passed around a cathode and an electric arc is established between the anode and cathode. A powder feed line or conduit is connected between the anode and a powder feed source. The feed line has a straight section along a portion of its length terminating at the axial bore of the anode. The straight section of feed line has a ratio of length to internal diameter at least about 4.8, preferably 10 and even more preferably 15.

Abstract: The present invention relates to a plasmatron for a plasma coating apparatus including an anode having an axial bore through which gas is passed around a cathode and an electric arc is established between the anode and cathode. A powder feed line or conduit is connected between the anode and a powder feed source. The feed line has a straight section along a portion of its length terminating at the axial bore of the anode. The straight section of feed line has a ratio of length to internal diameter at least about 4.8, preferably 10 and even more preferably 15.

Abstract: This invention provides a method and apparatus for improved arc initiation during Gas-Metal Arc welding. The unstable period at the arc start is a period when increased spatter is produced and increased fume is generated and defects such as unacceptable weld bead profiles, porosity and inadequate penetration occur. It has been observed that initiating the arc using a substantially higher average arc current and thereafter switching the power supply to a CV mode for the remainder of the Gas-Metal Arc welding operation decreases the arc initiation period and the instability produced during this arc start period. Initiating the arc using a CC supply and then dynamically switching on-line the power supply to CV operation provides a means of decreasing the arc initiation period and the amount of instability produced during the arc initiation period. Power supplies for Gas-Metal Arc welding and other applications requiring on-line switching between CC and CV are disclosed.

Abstract: A machine tool or die that is fabricated from thermally spray-formed steel is repaired on the factory floor by first cleaning the area to be repaired to removed all dirt and impurities. Next the surface is prepared by means of preheating the surface with propane torches at a rate not exceeding 50° Centigrade per hour to boil off the moisture in the tool. The weldment is formed by the TIG welding process and then finished by conventional machining, grinding and polishing.

Abstract: The method of the present invention includes placing a solid dopant in or near the nozzle of a DC arc jet. According to one embodiment of the invention, the interior surface of an arc jet nozzle is coated with a layer of copper by brushing the surface with a copper brush. According to another embodiment of the invention, the interior surface of an arc jet nozzle is coated with a layer of copper by plating it with copper. According to another embodiment of the invention, a copper cylinder is placed inside an arc jet nozzle. Apparatus according to the invention include a DC arc jet with a solid dopant placed in or near the nozzle according to one of the methods described. Diamonds according to the invention are conductive diamonds formed by a plasma jet process where a solid dopant was placed in or near the nozzle according to one of the methods described.

Abstract: A plasmagenic gas comprises a ternary mixture of helium, argon and hydrogen. The gas contains less than 30% helium, at least 55% argon, and from 5.5 to 15% hydrogen. The gas is energized to form a plasma. A powder of a refractory or metallic material is introduced into the plasma.

Abstract: A plasma arc torch includes a housing having a nozzle at one end with a central orifice. An electrode extends into the orifice for producing a plasma arc. A port is disposed in the nozzle adjacent the orifice for injecting powder into the arc. The port includes an outlet, an inlet, and a reniform manifold extending therebetween for laterally distributing the powder about the nozzle orifice. In this way, the powder may be carried to the torch underwater and is distributed circumferentially about the plasma arc while simultaneously diffusing its carrier gas.

Abstract: A process for post processing a part that has a Nitinol coating applied by plasma spraying or PVD coating gives the Nitinol desirable properties of toughness and malleability. It also produces a layer of surface material that is extremely hard, chemically non-reactive, electrically and thermally insulating. The process includes selecting a part that has a surface coating of Nitinol applied by plasma spraying or PVD coating and polishing the surface coating to give it a smooth and shiny surface. The polished surface is then cleaned to remove all polishing residue. The surface of the Nitinol coating is heated a temperature in a range of about 400° C. to 900° C.; and is rapidly cooled by forced air flow over the surface coating or by low temperature air or liquid immersion. Thereafter, the outer surfaces of the layer of surface material may be repolished and reheated as before to enhance the layer of thermally produced surface material.

Abstract: The high-velocity oxygen-fuel or air-fuel apparatus and method to apply low-oxidized and high-density coatings and bulk materials by spraying of non-fused particles, said apparatus comprises a catalytic member in internal burner. Metallic or ceramic catalyst of the catalytic member allows stable combustion at gas temperatures below the melting point of spraying material. Lowering of combustion temperature occurs when increasing the pressure and flow rate of the oxidizer or fuel over stoichiometrical or when adding an inert gas into combustible mixture. The catalytic member contains a catalyst selected from the group of noble metals, or binary oxides of the noble metal and rare earth metal, or other high temperature resistant catalyst capable to lower an ignition temperature of the oxidizer and fuel mixture.

Abstract: A nozzle-injector was designed and fabricated for plasma deposition of thin-film coatings using a wall-stabilized arc torch as the plasma generator. The design of the nozzle-injector controls the injection, ionization, and reaction of the reagents, and these functions, in turn, determine the coating deposition rate, coating area, coating composition, and coating quality.

Abstract: A method of brazing, with the use of a plasma forming device (1) having a non-consumable electrode (2), comprises the following steps of operation. A first gas is supplied to said plasma forming device (1). A plasma flow is formed of said first gas by applying a voltage between said electrode (2) and an electrical terminal (7). The plasma flow is directed towards a work piece (7). Braze material (10) to be melted by said plasma flow is provided. Furthermore, a second gas may be supplied for shielding said plasma flow from the surrounding atmosphere. At least one of said first and second gas comprises a principal inert component including at least argon and in a minor amount an active component.