Abstract: A shaped body is formed by cold-pressing a powdered material into a desired shape and then providing thereon a surface layer of a material having a lower melting point than the powder of the shaped body. The shaped body is then placed in a furnace connectable to vacuum equipment, wherein the pressure is first lowered to a value lower than atmospheric pressure and then the temperature is increased so that the material of the surface layer melts. Thereafter the body is isostatically hot-pressed under the direct influence of an inert, gaseous pressure medium, the powder particles being thus bound together to high density by pressure sintering.

Abstract: An electrical bushing is provided to facilitate the passage of electrical conductor leads from thermocouples or the like through a pressure barrier. The bushing includes a casing and a deformable, resilient, elastic plug which is disposed in a central conductor receiving bore of the casing in surrounding relationship to the conductors. Thus, when the plug is compressed in a direction axially of the casing, the plug tends to expand laterally radially and into sealing contact with the internal surfaces of the bore and with the electrical conductors.

Abstract: Disclosed is a method and structure for manufacturing solid bodies from a quantity of powder. The powder is preformed and the preform is enclosed in a casing provided with an evacuation nozzle. The preform and the casing are preheated and the preform is degassed by evacuating the casing through the nozzle after the casing has been appropriately evacuated. The nozzle is then sealed by heating the same to forging temperatures, compressing the end thereof which is remote from the casing, cutting the compressed end of the nozzle to present a straight edge and thereafter welding the nozzle shut along said edge. After the nozzle has been sealed the same is enclosed in and surrounded by a gas tight hood and the space between the hood and the nozzle is filled with a fill material which may be a powder, an annular solid body or a combination of such body and a quantity of powder.

Abstract: A high temperature-high pressure furnace which includes a cylindrical pressure chamber formed of a hollow cylindrical wall and two end closures therefor, a cylindrical sheath positioned within the cylindrical wall to provide a gap therebetween, and heaters positioned within the cylindrical sheath in order to provide a furnace space therewithin. The sheath at one end is sealingly connected to one of the end closures and at the other end is provided with a channel to provide fluid communication between the furnace space and the gap when an insulating lid is positioned over this other end of the sheath. The end closure to which the sheath is sealingly connected is provided with passageways which allow for fluid circulation therethrough and between the gap and the furnace space.

Abstract: For hydrostatically hot pressing bodies of borides, carbides or nitrides of titanium, zirconium or chromium from a powder having an excess of boron, carbon or nitrogen, the power is enclosed in a sealed container of a material which forms compounds with boron, carbon or nitrogen which have a melting point at least equal to that of the material of the container. Container materials may be for example metals from Group IVb of the Periodic System, particularly titanium and zirconium or their alloys in the case of titanium or chromium compounds and zirconium or zirconium base alloys in the case of zirconium compounds. This allows pressing at temperatures of up to 1700.degree.-1800.degree. C, which is high enough to cause bonding between the powder grains.

Abstract: A cylindrical elongated furnace for treating material at high temperature in a gaseous atmosphere under high pressure includes a vertical cylindrical pressure chamber for confining gas under pressure and a furnace space surrounded by a cylindrical heater formed of electrical resistor elements and insulation surrounding the furnace space and the heater. The insulation is formed by a cylindrical insulating sheath. The heater is built up of ceramic elements which form a cylinder with annular channels for the electrical resistor elements and supporting insulation surrounding and holding the ceramic elements together, such insulation having a low gas permeability and being formed of several layers of a tight felt impregnated with a hardening component. The leads for the heating elements are flat vertical elements arranged on the outside of the ceramic elements and formed with one or more bights projecting into the annular channels to reduce the free hanging length of the leads.

Abstract: In a cylindrical elongated furnace for treating materials at high temperature in a gaseous atmosphere under high pressure, there is a vertical cylindrical pressure chamber forming a furnace space surrounded by a cylindrical heater, with an insulating sheath around the furnace space and the heater formed of a number of metal tubes with insulation between them. At least one of the metal tubes is suspended from a supporting member at the upper part of the insulating sheath and is provided at its lower part with a number of slots extending upwardly from the bottom edge.

Abstract: A cylindrical elongated furnace for treating material at high temperature in a gaseous atmosphere under high pressure includes a vertical cylindrical pressure chamber for confining gas under pressure and a furnace space surrounded by a cylindrical heater formed of electrical resistor elements and insulation surrounding the furnace space and the heater. The insulation is formed by a cylindrical insulating sheath. The heater is built up of ceramic elements which form a cylinder with annular channels for the electrical resistor elements and supporting insulation surrounding and holding the ceramic elements together, such insulation having a low gas permeability and being formed of several layers of a tight felt impregnated with a hardening component. The leads for the heating elements are flat vertical elements arranged on the outside of the ceramic elements and formed with one or more bights projecting into the annular channels to reduce the free hanging length of the leads.