Abstract: In a method of impregnating carbon electrodes, a step of heating and drying carbon electrodes is separately juxtaposed to a step of pitch impregnation and cooling so that respective palettes are transported on separate courses for the respective steps, and at a position where said courses approach each other, the electrodes are transferred from a palette for said heating and drying step to a palette for said impregnation and cooling step so that the palette in the step of impregnation and cooling does not pass through a heating and drying furnace in the other step.

Abstract: Low-cost polycrystalline silicon solar cells supported on substrates are prepared by depositing successive layers of polycrystalline silicon containing appropriate dopants over supporting substrates of a member selected from the group consisting of metallurgical-grade polycrystalline silicon, graphite and steel coated with a diffusion barrier of silica, borosilicate, phosphosilicate, or mixtures thereof such that p-n junction devices are formed which effectively convert solar energy to electrical energy. To improve the conversion efficiency of the polycrystalline silicon solar cells, the crystallite size in the silicon is substantially increased by melting and solidifying a base layer of polycrystalline silicon before depositing the layers which form the p-n junction.

Abstract: A process for producing flexible graphite material comprises incorporating expanded graphite material with boric acid, compression molding the resulting mixture and, if desired, heating the resulting molding while under compression. This invention also relates to the flexible graphite material produced by the process.

Abstract: The invention provides a more economical carbon-fiber-reinforced carbon surfaced friction member, such as a brake disc, by replacing a disc which is of fiber-reinforced carbon throughout its thickness by a disc in which a fiber-reinforced surface layer is bonded to a base of a less expensive material, such as bulk graphite. A textile may be applied to the base and carbonized and carbon deposited on the textile layer by the multiple impregnation process or the chemical vapor deposition process. In the latter process the base is preferably heated above the temperature of the textile layer, e.g. by electrical induction or resistance, to obtain carbon deposition from the base outward through the textile layer.

Abstract: Polycrystalline silicon films useful in preparing solar cells primarily for terrestrial application are prepared by a plasma spraying process. A doped silicon powder is injected into a high temperature ionized gas (plasma) to become molten and to be sprayed onto a low-cost substrate. Upon cooling, a dense polycrystalline silicon film is obtained. A p-n junction is formed on the sprayed film by spray deposition, diffusion or ion implantation. A sprayed junction is produced by plasma spraying a thin layer of silicon of opposite polarity or type over the initially deposited doped film. In forming a diffused junction, dopant is applied over the surface of the initial plasma-sprayed film usually from the vapor phase and heat is used to cause the dopant to diffuse into the film to form a shallow layer of opposite polarity to that in the original film. A junction is also formed by implanting dopant ions in the surface of the originally deposited film by the use of electrical fields.

Abstract: The present invention relates to heavy-current electrical engineering, and more particularly to carbon-graphite brushes characterized by high wear resistance and low adhesive capacity of the brush dust, said brushes being intended for operation in commutator machines under moderate or heavy commutation conditions at an operating temperature of the sliding contact from 200.degree. to 250.degree. C, and to a method for manufacturing same.Carbon-graphite brushes for electric machines are made of a material which, after impregnation and heat treatment of the organic impregnation compound contains a dry residue evenly distributed through out the entire bulk volume thereof, the dry residue being a mixture of melamine-glyptal resin with a metal linoleate, in a polymerized state.

Abstract: The disclosure relates to a method of upgrading metallurgical grade silicon to semiconductor grade for making low cost silicon devices and particularly solar cells. This is accomplished by passing conductive fibers such as graphite or the like which are compatible with the later processing steps through an area which is cooled below 700.degree. C and which contains silicon difluoride and a proper N-type dopant. At these temperatures, the silicon difluoride gas will break down into pure silicon which will deposit onto the fiber with the formation of silicon tetrafluoride gas which is then recycled into a further chamber. In the further chamber, the gaseous silicon tetrafluoride is mixed with the impure metallurgical grade silicon at temperatures above 700.degree. C to form the silicon difluoride gas which is then fed into the former chamber for deposition of pure silicon onto the continuously moving fibers of graphite or the like.

Abstract: Low-cost polycrystalline silicon cells supported on substrates are prepared by depositing successive layers of polycrystalline silicon containing appropriate dopants over supporting substrates of a member selected from the group consisting of metallurgical-grade polycrystalline silicon, graphite and steel coated with a diffusion barrier of silica, borosilicate, phosphosilicate, or mixtures thereof such that p-n junction devices are formed which effectively convert solar energy to electrical energy.

Abstract: An electrostatic recording material having excellent recording characteristics is obtained by coating an electrically conductive substrate with a coating composition comprising an insulating polymer and pigment particles on which is adsorbed a fatty acid having at least five carbon atoms, ester or salt thereof, or resin acid or salt thereof.

Abstract: A method of applying to an anode for use in fusion electrolysis a coating for protection of the anode against surrounding influences, comprising delivering the material of the coating in finely dispersed form onto the anode with sufficient heat content and impact energy to cause adhesion between the material and the surface of the anode and consolidation of the material. Preferably the material is applied by means of a plasma burner and, for an anode to be used for the electrolytic production of aluminium, includes aluminium oxide and facultatively aluminium, the thickness of the coating beeing about 0.1 to 1.0 mm.

Abstract: Carbon articles, particularly carbon electrodes, are protected against corrosive attack in use by fusing material to the article, or applying material to the carbon article which under the conditions of its use is capable of fusing to the carbon article, to form a coherent coating of protective material over only that part of the carbon article liable to corrosive attack when the article is in use.