Abstract: The present document describes a composite material adapted to resist degradation by an erosive agent. The composite material comprises a steel base and crystals embedded in the steel base. At least 50% of the crystals have an elongated portion. Optionally, the composite material comprises an external surface for exposure to the erosive agent. At least 50% of the elongated portions are transverse to the external surface. A filler material is also described for forming the composite material on a ferrous surface by welding. The filler material comprises iron, carbon, boron, molybdenum and silicon. Methods are also described form forming the composite material.

Abstract: The present document describes a composite material adapted to resist degradation by an erosive agent. The composite material comprises a steel base and crystals embedded in the steel base. At least 50% of the crystals have an elongated portion. Optionally, the composite material comprises an external surface for exposure to the erosive agent. At least 50% of the elongated portions are transverse to the external surface. A filler material is also described for forming the composite material on a ferrous surface by welding. The filler material comprises iron, carbon, boron, molybdenum and silicon. Methods are also described form forming the composite material.

Abstract: A method of on site application of an erosion resistant coating. When deposited on the surface of a metallic substrate, the coating comprises hard ferroboride phases bound with a ductile metallic phase. The ductile metallic phase is selected from metals which have a low affinity for oxygen. The preparation and composition of a cored wire adapted for use in application of the erosion resistant coatings are also disclosed.

Abstract: Abrasion-wear resistant thermal sprayed stainless steel based coatings are disclosed, particularly arc sprayed stainless steel coatings containing titanium diboride crystals which impart hardness to the soft stainless steel matrix and enhance their resistance to hard abrasive media. There is also disclosed a process for making core wires composed of stainless steel sheaths and cores composed of a mixture of titanium diboride, stainless steel and certain additives. During the thermal spraying operation, the stainless steel sheath and the core material melt to form a composite coating containing fine hard titanium boride crystals dispersed within stainless steel. The arc sprayed stainless steel based coatings are more resistant to abrasion wear than solid pieces of type 304 stainless steel and other arc-sprayed stainless steel-based coatings available on the market.

Abstract: A process for synthesizing TiC composite materials containing a fine dispersion of TiC crystals in a metallic matrix. The matrix may contain one or more of metals selected from A1, Co, Cr, Cu, Fe, Mo, Ni and Ti. The process comprises rapid heating of a mixture of titanium alloys with carbon, preferably by arc melting or thermal spraying. This rapid heating step is also effective when the starting materials contain titanium, other metals and carbon.

Abstract: A zinc-based alloy comprising about 50 to 90 weight percent zinc and about 10 to 50 weight percent of at least one other metal selected from the group consisting of nickel, cobalt and iron. The zinc-based alloy according to the invention is particularly suitable for use as coating material for producing thermal-sprayed coatings having improved corrosion resistance and adherence.

Abstract: There is described a method and an apparatus wherein particles and a carrier gas are injected under pressure into a plasma flame. The particles are completely melted and are theraefter propelled onto a substrate to produce a coating thereon. According to the invention, the speed of the particles is slowed down and the flow of the gas carrier is adjusted, such as by disposing a cyclone ahead of the plasma flame, so as to provide an efficient injection of the particles in the center of the plasma flame.

Abstract: There is described a coating providing an anti-oxidant barrier for carbon based material against oxidation at high temperature (temperature higher than 500.degree. C.), more particularly for graphite electrodes used in electric arc furnaces. The coating comprises at least a first layer of metallic titanium or titanium alloy which is applied directly on the carbon-based material, e.g. graphite, and a second layer which comprises a mixture of silicon carbide and aluminum alloy, the second layer being applied on the first layer. This coating substantially extends the life of the carbon-based material. There is also disclosed a method of producing this coating by applying the two layers onto a carbon-based material such as graphite.

Abstract: There is disclosed a process for coating particles, such as ceramic, metallic and organic cores, with fine powder, such as ceramic, metal, organic or carbon powder. The process comprises providing a mixture comprising the particles and a binder which is capable of slowly melting to viscous state. Then the mixture is tumbled while slowly heating it to enable the binder to reach the viscous state while allowing the particles to be substantially covered with the binder. The next step includes cooling the mixture to about room temperature and thereafter breaking up the particles that may have agglomerated during the tumbling and heating to give individual particles covered with the binder. As a final step, the fine powder is added to the individual binder covered particles and the mixture is tumbled and heated again to the viscous state under conditions effective to provide a coating of the fine powder on the particles.

Abstract: There is disclosed a process for synthesizing TiB.sub.2 composite materials containing a metallic phase. The preparation of these composites comprises providing mixtures of titanium alloys which in addition to at least 30 wt. % titanium also contain F, Ni, Al, Mo, Cr, Co, Cu or mixtures thereof, and boron or ferroboron, reacting these mixtures by local igniting and exothermic reaction or by heating or melting, resulting in the synthesis of composite material containing fine TiB.sub.2 crystals dispersed in a fine metallic phase which is derived from the metallic element previously alloyed or combined with the titanium of the titanium alloys or the metallic element or elements contained in the ferroboron. By leaching out the metallic phase, fine TiB.sub.2 powders may be obtained. Parts and coatings can also be obtained. The parts are normally obtained by treating the TiB.sub.2 material by powder metallurgic techniques. Coatings may be obtained by thermo or plasma spray depositing on a substrate.

Abstract: The laser-surface coupler is used to uniformly irradiate a well defined surface area with a laser beam. The coupler includes a lower masking section and an upper section to form a cavity. The masking section has inner surfaces which are highly reflective and lustrous, and an aperture to define the surface area to be irradiated. The upper section has an opening to receive the laser beam into the cavity, and a highly reflective and diffuse inner surface to reflect and diffuse any radiation reflected to it from the irradiated surface. The coupler recycles any reflected radiation from the laser beam increasing the absorption coefficient and the irradiated surface is precisely defined by the masking section without loss of energy.