Abstract: Process for producing fumed silica powder with a decreased silanol group density, comprising subjecting a fumed surface untreated silica powder with a silanol density dSiOH of at least 1.2 SiOH/nm2 and a particle size d90 of not more than 10 ?m, to thermal treatment at a temperature of 350° C. to 1250° C. for 5 min to 5 h, wherein the temperature and the duration of the thermal treatment are chosen so that dSiOH of the silica is decreased by 10%-70% relative to dSiOH of the employed thermally untreated silica, wherein the thermal treatment is carried out while the fumed silica powder is in motion, followed by optional surface treatment. Surface unmodified and modified fumed silica powders obtained by this process and the use thereof.

Abstract: The invention provides fumed silica granules having a BET surface area of 20 m2/g to 500 m2/g; a number average particle size d50 of 350 ?m to 2000 ?m; a span (d90?d10)/d50 of particle size distribution of 0.8-3.0; a bulk density of more than 0.35 g/mL; a pore volume for pores >4 nm of not more than 1.5 cm3/g, process for its preparation and use thereof as a catalyst carrier, a carrier for liquid substances, in cosmetic applications, for thermal insulation, as pharmaceutical excipient, in producing thermally treated silica granules, as an abrasive, as a component of a silicone rubber.

Abstract: Fumed silica powder, surface treated with a surface treatment agent selected from the group consisting of organosilanes, silazanes, acyclic polysiloxanes, cyclic polysiloxanes, and mixtures thereof, wherein the powder has: a) a number of silanol groups relative to BET surface area dSiOH of at least 0.85 SiOH/nm2, as determined by reaction with lithium aluminium hydride; b) a methanol wettability of more than 40% by volume of methanol in methanol-water mixture; c) a tamped density of not more than 200 g/L.

Abstract: Surface-treated fumed silica, with a tribo-electro static charge of ?500 ?C/g to +500 ?C/g, a ratio of the tribo-electro static charge to BET surface area of ?3.5 ?C/m2 to +3.5 ?C/m2, a methanol wettability of at least 20% by volume methanol in methanol/water mixture, a ratio of carbon content to BET surface area of at most 0.020 wt. %*g/m2, a process for its preparation and the use thereof.

Abstract: A method can produce a thermoelectric component or at least a semifinished version of the thermoelectric component. The method includes: a) providing a substantially planar substrate; b) providing a pulverulent thermoelectrically active material; c) pressing the active material to form green bodies; d) inserting green bodies into through-holes of the substrate; e) arranging the substrate with the green bodies inserted therein between two substantially planar electrodes; f) contacting face ends of the green bodies with the electrodes; g) exposing the green bodies to an electric current flowing between the electrodes; h) exposing the green bodies to a pressure force acting between the electrodes; i) sintering the green bodies to form thermolegs; and k) levelling the substrate and the thermolegs accommodated therein by bringing them closer to the electrodes while maintaining the parallelity thereof.

Abstract: A method can produce a thermoelectric component or at least a semifinished version of the thermoelectric component. The method includes: a) providing a substantially planar substrate; b) providing a pulverulent thermoelectrically active material; c) pressing the active material to form green bodies; d) inserting green bodies into through-holes of the substrate; e) arranging the substrate with the green bodies inserted therein between two substantially planar electrodes; f) contacting face ends of the green bodies with the electrodes; g) exposing the green bodies to an electric current flowing between the electrodes; h) exposing the green bodies to a pressure force acting between the electrodes; i) sintering the green bodies to form thermolegs; and k) levelling the substrate and the thermolegs accommodated therein by bringing them closer to the electrodes while maintaining the parallelity thereof.

Abstract: The invention relates to a method for producing a thermoelement for a thermoelectric component, in which method: with the aid of a plasma flame, a diffusion barrier made of nickel is applied to a thermoelectric active material; or, with the aid of a plasma flame, a contact-facilitating layer made of tin is applied to a diffusion barrier made of nickel. The invention also relates to a thermoelectric component comprising thermoelements which are produced correspondingly. The aim of the invention is to further develop the conventional plasma spraying technique such that it can be used to produce thermoelements on an industrial scale. To achieve this aim, nickel particles or tin particles are used, which particles conform to a particular specification with regard to their sphericity.

Abstract: The invention relates to a method for producing a thermoelectric component or at least one semi-finished product of same, in which a multiplicity of thermolegs made of a thermoelectrically active material are introduced into an essentially planar substrate made of an electrically and thermally insulating substrate material such that the thermolegs extend through the substrate essentially perpendicular to the substrate plane, and in which the active material is provided in pulverulent form, is pressed to give green bodies and is then sintered within the substrate to give thermolegs. It is based on the object of refining the method of the generic type mentioned in the introduction so as to increase the freedom of choice of the thermally and electrically insulating substrate material.

Abstract: The invention relates to a method for producing a thermoelectric component or at least a semifinished version thereof, in which at least one thermoelectric active material in dry powder form is introduced into at least some of the holes of a perforated template. It addresses the problem of specifying a method which can be conducted in a particularly economically viable manner. The problem is solved by virtue of the active material remaining in the holes of the template, and the template filled with active material becoming a constituent of the thermoelectric component produced.

Abstract: The invention relates to a method for producing a thermoelectric component or at least one semi-finished product of same, in which a multiplicity of thermolegs made of a thermoelectrically active active material are introduced into an essentially planar substrate made of an electrically and thermally insulating substrate material such that the thermolegs extend through the substrate essentially perpendicular to the substrate plane, and in which the active material is provided in pulverulent form, is pressed to give green bodies and is then sintered within the substrate to give thermolegs. It is based on the object of refining the method of the generic type mentioned in the introduction so as to increase the freedom of choice of the thermally and electrically insulating substrate material.

Abstract: The invention relates to a method for producing a thermoelectric component or at least a semifinished version thereof, in which at least one thermoelectric active material in dry powder form is introduced into at least some of the holes of a perforated template. It addresses the problem of specifying a method which can be conducted in a particularly economically viable manner. The problem is solved by virtue of the active material remaining in the holes of the template, and the template filled with active material becoming a constituent of the thermoelectric component produced.