Abstract: In one aspect, the present invention comprises providing an additive or aggregate to be applied directly to one or more of the components of a ceramic coating and which is constituted by carbonate apatites particles which are maintained as aggregates within a matrix of silicoaluminates at firing temperatures of the ceramic coatings, where the main function of these aggregates is to provide the ceramic coating properties selected from the group comprising: low effusivity, wear resistance, resistance to chemical attack and resistance to staining. In other aspects, the present invention comprises providing a ceramic coating incorporating said additive and a method for providing a ceramic coating with properties selected from the group comprising: low effusivity, wear resistance, resistance to chemical attack and resistance to staining.

Abstract: In one aspect, the present invention comprises providing an additive or aggregate to be applied directly to one or more of the components of a ceramic coating and which is constituted by carbonate apatites particles which are maintained as aggregates within a matrix of silicoaluminates at firing temperatures of the ceramic coatings, where the main function of these aggregates is to provide the ceramic coating properties selected from the group comprising: low effusivity, wear resistance, resistance to chemical attack and resistance to staining. In other aspects, the present invention comprises providing a ceramic coating incorporating said additive and a method for providing a ceramic coating with properties selected from the group comprising: low effusivity, wear resistance, resistance to chemical attack and resistance to staining.

Abstract: A gas-blowing device used in an apparatus for carrying out a process for producing pore-free cast-on-strap joints for lead-acid batteries. The device includes a metallic pipe closed at both ends having a plurality of groups of aligned gas outlets, gas inlets and inner plugs, all of which are evenly distributed along the pipe's length, and leveling plates. The gas-blowing device is used to give a simultaneous final cleaning and drying to a plurality of negative and positive plate lug surfaces immediately after water rinsing the plate lugs under ultrasonic vibration and prior to joining the plate lugs by the cast-on-strap process. This is done by means of gas jets coming out at high pressure from the gas outlets, and which are directed towards the plate lug surfaces. A uniform distribution of gas pressure and flow rate for all gas outlets, as well as a correct direction for all gas jets, are assured along the entire pipe's length.

Abstract: An apparatus for cleaning and chemical activation of a plurality of plate lug surfaces. The apparatus includes an ultrasonically-stirred flux vessel, an ultrasonically-stirred rinsing water vessel and a gas-blowing device contained inside a dirt collection vessel. Each vessel has an independent movement capability in the upward or downward directions, and all three vessels are mounted on a common supporting frame which allows their simultaneous horizontal displacement. When coupled to a conventional cast-on-strap machine, the apparatus allows the manufacture of pore-free cast-on-strap joints for lead-acid batteries.

Abstract: A method for producing pore-free cast-on-strap joints for lead-acid batteries including the steps of cleaning a plurality of positive and negative plate lugs by a combined action of flux and ultrasonic vibration, water rinsing the plate lugs under ultrasonic vibration, and drying the plate lugs by gas blasting. The gas blasting occurs prior to the formation of the cast-on-strap joint. The cast-on-strap joint is formed by introducing the plate lugs into a molten lead-based strap alloy contained in a strap mold and solidifying the molten strap alloy in the strap mold.

Abstract: This document discloses a method for bonding a calcium phosphate coating to stainless steels or cobalt base alloys for bioactive fixation of artificial implants. The method consists essentially of the following successive steps: applying and thermally diffusing a layer of titanium or its alloys into the stainless steel or cobalt base alloy substrates, applying a calcium phosphate coating and thermally diffusing Ca.sup.2+ and PO.sub.4.sup.-3 ions of the calcium phosphate into the intermediate layer of the titanium or its alloys and finally, the hydrothermal processing of the calcium phosphate coating.

Abstract: The purpose of this invention is to present an apparatus consisting of a graphite rod, a vibration signal sensor, a signal processing unit, a data processing unit, and a data display unit to indicate the oxygen content of a copper melt. As such graphite rod is immersed into the molten metal it vibrates and the level of vibration is statistically correlated to the level of dissolved oxygen in the copper melt.

Abstract: A method for producing a weak resistance injection element for introducing ases into molten metals.The injection element includes an assembly of at least two high density refractory components. At least the upper high density refractory component is made by isostatic pressing of ceramic powders followed by a double heat treating process which are selected according to the liquid metal to be melted/refined in the metallurgical vessel where the injection element is going to operate.

Abstract: Wax, alloy or plastic molds for containers used in hot isostatic pressing of metal and/or ceramic powders are surface conditioned for electroplating, coated with several metallic layers and removed from the resulting container.

Abstract: A method to improve the service life of gas injection devices is disclosed.A porous mushroom with controlled permeability is formed, previously to the element installation, in the tip of said element by a thermal spray process.By controlling gas flow rate and pressure during the mushroom formation, the gas permeability in said mushroom is controlled.The sprayed materials are high melting point ceramics, metal compounds or synthetic slags.

Abstract: The present invention relates to a method and a fluid injection device for quick replacement, even in the red hot conditions, in a metallurgical reactor. The method comprises the external extraction of the injection device which is composed of an inner extractable blowing element and wear resistant block, element the blowing element secured in the wear resistant block and forming together the injection device. The quick interchange is first performed by extracting the inner blowing element, then installing a special extractor device in the space where the blowing element was and then extracting the wear resistant block by applying a force, in the opposite direction of the gas flow, through the bottom end of the extractor device. The extractor device has a special design so, when a force is applied at its bottom end, an expansive occurs at the upper end making the external extraction of said wear resistant block easier.

Abstract: This invention relates to a method and a device to produce a coating from metal powder metallurgically bonded to a metallic part, said metal powder being compacted over the surface of said metallic part to form the coating using cold isostatic pressing, then coupling an open metallic container to the coating leaving a space between said open metallic container and said coating, completely filling the space between the metallic container and the coating with a ceramic material and sealing, so that the ceramic material exerts pressure due to the thermal expansion over the coating during the heating in a sintering furnace in order to get a metallurgical bond between the metallic part and the coating and simultaneously sintering the coating to achieve the desirable the desirable thickness and the required properties.

Abstract: A method for the improvement of the process for the refining of liquid metals by means of the injection of natural gas.It is upon the lab and semi-industrial plant experience of the inventors of the present invention, that it was found that during the injection of natural gas into liquid metals, there is substantially no cracking of methane under usual conditions of pressure and temperature in the refining processes.In such conditions, natural gas can be used as inert gas in metallurgical processes with technical and economical advantages over inert gases, introducing it through the bottom of the liquid bath. This practice has in addition, the property of reinforcing the process conditions, oxidizing or reducing, according to the slag in the molten bath.

Abstract: A device for bubbling gases through molten metal and specially adapted to be used in ladles or metallurgical vessels where it is necessary to stop the flow of gas without risk of penetration of liquid metal through the device. The device includes a metal casing holding a number of refractory plates or concentric cylinders that have opposed, specially roughened surfaces and that have their roughened surfaces juxtaposed without inserts or slots between them. The plates or cylinders can be roughened by controlled shot blasting to provide a plurality of randomly arranged surface discontinuities that define a plurality of unoriented flow passages when the plates or cylinders are placed in contacting, face-to-face relationship. Gas flow rates substantially greater than 5 liters per second can be obtained, and the device prevents molten metal flow therethrough when the gas flow has been cut off.

Abstract: A process to improve electric arc furnace steelmaking. The efficiency increase is due to the metal-slag stirring that is produced by bottom gas injection through gas permeable ceramic elements. The permeable elements are not penetrated by the liquid metal, which does not stop the gas flow.The process is carried out in combination with a furnace charging door stopper device. The device avoids liquid ejections through the furnace charging door during the injection periods. The electric arc furnace steelmaking generalized practices are more effective when the molten metal is being stirred by gas injection, by increasing the metal-slag and the slag-atmosphere interphase area. When the stirring gas is natural gas, the process conditions, oxidizing or reducing, are reinforced according to the slag in the bath.