Abstract: A method for producing a solar crucible includes providing a crucible base body of transparent or opaque fused silica having an inner wall, providing a dispersion containing amorphous SiO2 particles, applying a SiO2-containing slip layer to at least a part of the inner wall by using the dispersion, drying the slip layer to form a SiO2-containing grain layer and thermally densifying the SiO2-containing grain layer to form a diffusion barrier layer. The dispersion contains a dispersion liquid and amorphous SiO2 particles that form a coarse fraction and a fine fraction with SiO2 nanoparticles. The weight percentage of the SiO2 nanoparticles based on the solids content of the dispersion is in the range between 2 and 15% by weight. The SiO2-containing grain layer is thermally densified into the diffusion barrier layer through the heating up of the silicon in the crystal growing process.

Abstract: Device for producing silicon blocks for photovoltaic applications, comprising a container for receiving a silicon melt with a base wall and at least one side wall, means for reducing the diffusion of impurities from at least one of the walls of the container into the silicon melt, wherein the means for reducing the diffusion of impurities comprise at least one covering element for the at least partial covering of at least one of the walls of the container.

Abstract: A method for producing a solar crucible includes providing a crucible base body of transparent or opaque fused silica having an inner wall, providing a dispersion containing amorphous SiO2 particles, applying a SiO2-containing slip layer to at least a part of the inner wall by using the dispersion, drying the slip layer to form a SiO2-containing grain layer and thermally densifying the SiO2-containing grain layer to form a diffusion barrier layer. The dispersion contains a dispersion liquid and amorphous SiO2 particles that form a coarse fraction and a fine fraction with SiO2 nanoparticles. The weight percentage of the SiO2 nanoparticles based on the solids content of the dispersion is in the range between 2 and 15% by weight. The SiO2-containing grain layer is thermally densified into the diffusion barrier layer through the heating up of the silicon in the crystal growing process.

Abstract: Method for producing a silicon ingot, comprising the following steps: providing a container to receive a silicon melt, providing a temperature control device to control the temperature of the silicon melt in the container, arranging raw material in the container comprising silicon and at least one nucleation agent to assist a heterogeneous nucleation in the silicon melt, and control of the temperature in the container for the directed solidification of the silicon melt, the nucleation agent comprising nanoscale particles.

Abstract: A device for the production of silicon blocks comprises a vessel for receiving a silicon melt, the vessel comprising a vessel wall comprising at least one side wall and a bottom as well as an inside and an outside and a central longitudinal axis, and means for creating a temperature field on the inside of the bottom, the temperature field having a temperature gradient at the bottom of the vessel which is perpendicular to the central longitudinal axis at least in some regions when the silicon melt cools down for crystallization.

Abstract: Device for producing silicon blocks for photovoltaic applications, comprising a container for receiving a silicon melt with a base wall and at least one side wall, means for reducing the diffusion of impurities from at least one of the walls of the container into the silicon melt, wherein the means for reducing the diffusion of impurities comprise at least one covering element for the at least partial covering of at least one of the walls of the container.

Abstract: Device for holding a silicon melt comprising a crucible, which partly surrounds an inner chamber for holding the melt, with a base and at least one side wall made of a base material, whereby the crucible comprises at least one equalizing means for equalizing mechanical thermal stresses.

Abstract: Method for producing a silicon ingot, comprising the following steps: providing a container to receive a silicon melt, providing a temperature control device to control the temperature of the silicon melt in the container, arranging raw material in the container comprising silicon and at least one nucleation agent to assist a heterogeneous nucleation in the silicon melt, and control of the temperature in the container for the directed solidification of the silicon melt , the nucleation agent comprising nanoscale particles.

Abstract: A method for producing silicon blocks comprises providing a crucible for receiving a silicon melt, with a base and a plurality of side walls connected to the base, attaching nuclei at least on an inner side of the base of the crucible, the nuclei having a melt temperature, which is greater than the melt temperature of silicon, filling the crucible with the silicon melt, solidifying the silicon melt beginning on the nuclei and removing the solidified silicon from the crucible.

Abstract: A device for the production of silicon blocks comprises a vessel for receiving a silicon melt, the vessel comprising a vessel wall comprising at least one side wall and a bottom as well as an inside and an outside and a central longitudinal axis, and means for creating a temperature field on the inside of the bottom, the temperature field having a temperature gradient at the bottom of the vessel which is perpendicular to the central longitudinal axis at least in some regions when the silicon melt cools down for crystallization.

Abstract: Device for the production of silicon blocks, the device comprising a vessel for receiving a silicon melt with a bottom, an inside, an outside and a central longitudinal axis and at least one support plate which is at least partially in direct contact with the bottom, and which forms a base together with the bottom, and means for generating an inhomogeneous temperature field on the inside of the bottom.

Abstract: A device for the production of silicon blocks comprising a vessel for receiving a silicon melt with at least one vessel wall, with the at least one vessel wall comprising a nucleation-inhibiting coating on at least part of an inside or with the at least one vessel wall consisting of a nucleation-inhibiting material.

Abstract: Oven for non-metal melting, in particular silicon melting, with a housing enclosing an interior, at least one mould arranged in the interior for receiving a non-metal melt, at least one electrical heating device enclosing, at least partially, the at least one mould for influencing the temperature of the non-metal melt, and a power supply device connected in an electrically conductive manner to the at least one heating device for providing the heating device with a time-variable current I(t), wherein the current I(t) has a frequency of 0.1 Hz to 1000 Hz and the current I(t) is of a magnitude sufficient for setting a predetermined temperature of the non-metal melt, the currents in the plurality, where necessary, of heaters having a defined phase position in respect of one another.

Abstract: Oven for non-metal melting, in particular silicon melting, with a housing enclosing an interior, at least one mould arranged in the interior for receiving a non-metal melt, at least one electrical heating device enclosing, at least partially, the at least one mould for influencing the temperature of the non-metal melt, and a power supply device connected in an electrically conductive manner to the at least one heating device for providing the heating device with a time-variable current I(t), wherein the current I(t) has a frequency of 0.1 Hz to 1000 Hz and the current I(t) is of a magnitude sufficient for setting a predetermined temperature of the non-metal melt, the currents in the plurality, where necessary, of heaters having a defined phase position in respect of one another.

Abstract: In a low pressure die casting apparatus, the properties of the rising pipe of sintered ceramic material for light metal melts is improved by a covering of heat-resistant material surrounding the upper part of the rising pipe.

Abstract: A gassing agitator for light metal melts made of thermal shock-resistant ceramic is described which consists of minimally machined ceramic tubes that are connected to one another using the insert and lock technique.

Abstract: Ceramics having principal phases of aluminum iron titanate and mullite corresponding to the overall chemical composition:50 to 62% by weight Al.sub.2 O.sub.3,36 to 49.5% by weight titanium oxide, expressed as TiO.sub.2,0.5 to 10% by weight SiO.sub.2, and0.2 to 15% by weight iron oxide, expressed as Fe.sub.2 O.sub.3,up to 1% by weight impurities,with the sum of Al.sub.2 O.sub.3, TiO.sub.2 and SiO.sub.2 being 100%,wherein the sum of the crystalline phases Al.sub.2 O.sub.3, TiO.sub.2, SiO.sub.2 (other than the principal phases) is less than 6% by weight, based on the sintered body, are useful where a ceramic having a high thermal-shock-resistance is required, such as exhaust port liner internal combustion engines, for example.

Abstract: Slip-cast ceramic component having an internal chamfer which is optionally interrupted by an internally projecting area, obtainable by providing a slip cast blank of the ceramic component with uniform thickness and desired internal configuration wherein the volume corresponding to the internal chamfer is outwardly disposed and which is removed by external machining to arrive at the geometry of the ceramic component. The component is useful, inter alia, as a spacer ring which serves for the positioning of honeycomb-shaped catalyst blocks in exhaust gas lines.

Abstract: Sintered ceramic material which comprises doped aluminum titanate and mullite having the composition:50-61.5% by weight Al.sub.2 O.sub.3,36-47.5% by weight titanium oxide, expressed as TiO.sub.2,2.5-5% by weight SiO.sub.2,with the sum total of the three components adding up to 100%, and which further comprises 0.3 to 1% by weight MgO and up to 1% by weight impurities, useful as, inter alia, filters, catalyst supports and internal combustion engine parts, are prepared by mixing and shaping materials of suitable composition and then sintering the shaped composition at temperatures of 1250.degree. to 1600.degree. C. over a holding time of 0.5 to 100 hours.

Abstract: A ceramic raw material mixture with improved processing properties comprising at least two chemically different raw material components, wherein at least two of the raw material components have the same type of cation on the surface thereof, at least one of the raw material components being coated with said type of cation and the coating, calculated as cation oxide, amounting to 0.01 to 6% by weight, based on the coated component, and all the raw material components having a surface with an isoelectric point of .ltoreq.pH 7.