Asea Aktiebolag

Sandvik Ab

Asea Ab

Abb Cerama Ab

Volvo Aero Corporation

Asea Cerama Ab

Bertil Mattsson

Jan Nilsson

Hans Larker

Jan Adlerborn

Marianne Collin

Robert Lundberg

Lars Pejryd

Leif Hermansson

Method for manufacturing composites

According to the present invention there is provided a method of manufacturing a compound body having at least one, partly covering layer on a porous body, whose pore system is evacuate by means of a subpressure which is applied on the porous body by a suction cup or the like and the body is dipped in a slurry of powdery components of the layer. The compound body is densified by sintering or other heat treatment, e.g., post-HIP.

Method of manufacturing a compound body and the resulting body

Method for isostatic or pseudo-isostatic pressing employing a

An object is manufactured from a powdered ceramic material while using isostatic pressing. The powdered material is thereby supplied with a temporary organic binder and is formed into a preformed powder body (10). A major part of the binder is removed from the preformed powder body by driving off under heating, whereas a minor part of the binder, required for keeping the powder body together, is retained in the powder body. The powder body is provided with a gas-permeable embedding material (14) of glass, the retained minor part of the binder then being removed by additional driving off under heating and preferably by also treating the powder body with the surrounding gas-permeable embedding material with an oxidizing gas. The gas-permeable embedding material is then made gas-impermeable by heating and the preformed powder body, freed from binder, with the surrounding gas-impermeable embedding material is subjected to isostatic pressing.

Method of manufacturing an object of a powdered ceramic material

When manufacturing an object of powdered material by isostatic pressing of a body (10), preformed from the powdered material, with a gaseous pressure medium, the preformed body is provided with a casing (19) of glass which is made gas-impermeable by heating before carrying out the isostatic pressing. Inside the glass casing there is arranged on the preformed body a barrier layer (11) which counteracts the penetration of melted glass from the enclosure in the preformed body. The barrier layer is built up of at least two layers, of which one layer (12) at least substantially consists of powdered boron nitride and one layer (13) of a mixture of powdered boron nitride and a powdered material with the ability, upon contact with glass from the casing in melted form, to make a layer containing boron nitride tighter.

Method of manufacturing an object of powdered material by isostatic

In the manufacture of an article of ceramic material, for example a bladed turbine wheel of silicon nitride, there is first formed a plurality of article parts, at least one of which is a shaped powder body formed from powder of ceramic material mixed with a plasticizer, after which the plasticizer is driven off by a suitable heating operation. The article parts are then assembled together into a configuration conforming to that of the article to be manufactured, and the assembled article parts are surrounded with a gas-impermeable layer, for example a layer of glass. Finally, the assembled parts are isostatically pressed at elevated temperature to form the assembled article parts into a dense, homogeneous article.

Method of manufacturing articles of ceramic material

An object is manufactured from a powdered material by isostatic pressing of a body, preformed from the powdered material, with a pressure medium, whereby the preformed body, in which at least the surface layer consists of a ceramic material in the form of a nitride, is surrounded by a casing which is rendered impenetrable to the pressure medium, before the isostatic pressing is carried out and the powder sintered. As the material in the casing there is used boron oxide or a glass containing boron oxide or a material forming glass while being heated, in which the content of boron oxide is sufficiently high for the glass--or the glass formed during heating--to be removable by water. The preformed body surrounded by the casing is subjected to a heat treatment for the formation of boron nitride on the surface of the preformed body, before the isostatic pressing is carried out. The casing is removed from the finished product by means of water or water vapor.

Method of manufacturing an object of a powdered material by isostatic

An object of ceramic or metallic material is manufactured by isostatic pressing of a body preformed from a powder of the metallic or ceramic material, the preformed body (10) then being embedded in glass, for example in a mass of glass particles (16) in a vessel (15) which is resistant to the temperature at which the sintering of the metallic or ceramic material is carried out, the material embedding the preformed body being transferred to a melt having a surface limited by the walls of the vessel, below which surface the preformed body is located, and a pressure necessary for the isostatic pressing of the preformed body then being applied on the melt by a gaseous pressure medium.

Method of manufacturing an object of metallic or ceramic material

Disclosed is a mandrel for a high pressure tube extrusion press. The mandrel comprises a tip member providing a tip adapted to be positioned in the die opening of the press to present an annular gap for tube extrusion, and a carrier for the tip member. The carrier has a threaded central tip member receiving bore for threadably receiving a threaded segment of the tip member therein. A divided ring shaped element is disposed between a flange on the tip member and the carrier in an annular space provided at the mouth of the bore to facilitate the assembly and disassembly of the mandrel and prevent inadvertent separation of the tip member from the carrier.

Growing community of inventors

Robertsfors, Sweden

Bertil Mattsson