Abstract: A steel substrate is provided with an aluminum intermediate layer and a boron layer. The aluminum intermediate layer provides a substantially improved adhesion of the boron layer. The boron layer is provided by a low-temperature CVD process.

Abstract: In the manufacture of tube glass, in which following the drawing of a tube from molten glass the inside surface of the tube is treated with a chemically reactive gas or gas mixture, a gas or gas mixture which is not reactive at the drawing temperature of the glass is dispensed into the tube in the direction of drawing. At a location in the tube where the tube has cooled down so far that the diameter is constant, the gas or gas mixture is made to react by means of a plasma which is generated in the tube.

Abstract: A steel substrate is provided first with an aluminum intermediate layer and then, by a CVD process, with an outer layer of boron.

Abstract: A device for the continuous measurement of the thickness of layers which are deposited on a substrate at low pressure, comprising a light source and two light conductors. Both light conductors are present in a pipe closed at one end by an optical window. Said end has an exchangeable sleeve which at one end comprises an optical window and which can be slid so as to fit the pipe in which the light conductors are present.

Abstract: A method of making an electric resistor having a negative temperature coefficient of resistance whose resistance body consists of p-type doped pyrolytic polycrystalline cubic silicon carbide.

Abstract: A lacquer-encapsulated carbon film resistor having a ceramic substrate coated with a carbon film, a silicon nitride layer, an organic lacquer layer and termination electrodes.

Abstract: An electrode for the electrochemical machining of electrically conductive workpieces, which electrode has a layer of polycrystalline silicon carbide via an insulator layer which is at most 0.5 .mu.m thick.

Abstract: In order to increase recording quality the electrode pin of a device for electrostatically printing characters consists of a whisker which is mounted to be electrically conductive in a metal holder. A whisker is by definition a monocrystalline member.

Abstract: An electric resistor having a negative temperature coefficient of the electrical resistance whose resistance body consists of p-type doped pyrolytic polycrystalline cubic silicon carbide.

Abstract: A method of growing silicon carbide whiskers from a gaseous phase by means of a vapor-liquid-solid mechanism on a substrate using iron in a finely divided state as a solvent for the silicon carbide.

Abstract: Electrode for electrochemically machining electrically conducting workpieces, in particular machining them by removal of material, which electrode is locally coated with a screening layer consisting of a polycristalline semiconductor material, which layer preferably comprises two component layers of p and n-conductivity type respectively.

Abstract: A method of manufacturing silicon carbide crystals in which a core of silicon dioxide is embedded in a mass of granular silicon carbide, or materials which form silicon carbide on heating this mass being heated to a temperature at which silicon dioxide volatilizes, i.e. above about 1500.degree.C, and the silicon carbide coheres. This leaves a cavity, formerly occupied by the silicon dioxide which is surrounded by silicon carbide. Heating is then continued at a temperature, above about 2500.degree.C, at which silicon carbide crystals are formed on the walls of the cavity.