Abstract: The invention relates to a protective coating on at least one electrical conductor and/or semiconductor, especially an electric sensor, in which a porous first protective coating is applied directly to the surface of the electrical conductor and/or semiconductor and a gas-tight second protective coating is applied at least to regions of the first protective coating.

Abstract: The invention relates to a method as well as to an electrochemical sensor for measuring the concentration of at least one predetermined gas in a gas mixture by means of an electrolyte provided with a first and a second surface-mounted electrode, which are exposed to the gas mixture together with the electrode connected to a voltage source, wherein the voltage source causes an electrical current flowing through the electrodes and electrolyte, which is dependent upon the ion concentration and is measured as an indicator of the gas concentration.

Abstract: The invention relates to a method to measure an electro-chemical activity of a non-metallic liquid layer lying on a molten bath by means of a measuring cell with an electro-chemical element which has an active part and with a counter electrode. The invention also relates to a measuring cell to measure an electro-chemical activity. In order to achieve exact measuring results of an electro-chemical activity with the least possible expenditure, the measuring cell is dipped through a non-metallic liquid layer into a molten bath, the active part of the electro-chemical element being surrounded by the non-metallic liquid layer of the material of this layer on insertion, this material being held at the electro-chemical element until after measuring the electro-chemical activity and the measurement being carried out after dipping the electro-chemical element into the molten metal within the molten bath. The electro-chemical element is especially developed to enable that the material to be measured adheres to it.

Abstract: A sensor arrangement for measuring the temperature of molten masses uses a receptacle having at least one strip-shaped or wire-shaped carrier and an opening on its upper side, with a thermoelement placed inside the receptacle. In order to make available a sensor arrangement for the exact determination of the liquidus temperature of molten cryolite, the receptacle is made of metal. A temperature measuring device with a sensor arrangement of this type, has at least one carrier mounted at its end facing away from the receptacle in a sleeve, the sleeve being detachably connected to a mounting device. In addition, a process for measuring the liquidus temperature of molten cryolite in a receptacle vibrates the receptacle during the cooling of the molten cryolite.

Abstract: An apparatus is provided for obtaining a sample coupon from a container of molten metal for the performance of metallographic microstructural evaluation. The apparatus comprises a housing formed of a material resistant to thermal breakdown, the housing having an exterior surface, a closed first end, and a second end including an opening sized and shaped for receiving and retaining a support member. The housing further includes an interior coupon chamber and a passageway extending between the coupon chamber and the exterior surface. The coupon chamber has at least one generally flat surface and a cross-sectional dimension of not less than seven square millimeters and not greater than 1,250 square millimeters.

Abstract: An apparatus for the measurement of the surface tension of liquids by means of a capillary tube for supplying gas, the tube having a connector and a nozzle, may be used in a measuring device. In order to create an apparatus that is easy to manufacture and handle, and that can be used reliably in a variety of liquids, the capillary tube is arranged, at least partially, in a crucible for receiving the liquid and is mounted on the wall of the crucible, whereby the connector is arranged outside the interior of the crucible. The connector is connected to the gas line of the measuring device and to a pressure sensor and/or a flow meter.

Abstract: A sampling device for molten metals with a sample chamber arranged in a paperboard tube has an inflow canal leading through the paperboard tube, the canal being formed essentially of a heat-resistant inflow tube, such that the outer end of the inflow tube ends below (inside) the outer circumference of the sampling device and is closed off by a delayed-action device. In order to create a sampling device in which the intrusion of contaminants into the sample chamber is prevented, especially slag particles, gas occlusion particles and particles of the paperboard tubes, the delayed-action device is constructed as a multi-layered cap, whereby between cap and paperboard tube an intermediate space is formed, which is filled with cement.

Abstract: A drop-in immersion probe for inserting into molten metal includes a generally cylindrical measurement head having an axis and a first axial end which is inwardly tapered toward the axis. The measurement head is made of a combination of materials having a combined density greater than the density of the molten metal. A sensor element extends outwardly from the first axial end of the measurement head proximate the axis and a slag cap covers the first end of the measurement head and the sensor element. A leadwire extends outwardly from the measurement head and has one end electrically connected to the sensor element. A portion of the leadwire extending outwardly from the measurement head is preferably covered by a protective sleeve of heat resistant material. In a preferred embodiment, the slag cap and the measurement head are covered with an ablative material to prevent the adherence of slag.

Abstract: An immersion probe for determining a liquidus temperature of a molten metal sample during solidification has a first refractory body with an immersion face, an interior sample chamber, and a passageway between the immersion face and an end wall of the chamber. A heat sink is positioned within the chamber adjacent the end wall and an insulating shield is positioned within the chamber adjacent the heat sink, each having an aperture corresponding to the inlet tube. The insulating shield sinks thermal energy from within the chamber at a second rate R.sub.2 slower than a first rate R.sub.1 of the interior walls of the chamber. A liquidus temperature sensor is positioned within the chamber away from the insulating shield. To determine the liquidus temperature, the probe is immersed in the molten metal, and a molten metal sample flows into the chamber through the passageway. When the flow ceases, the heat sink solidifies an adjacent portion of the molten metal and seals the sample within the chamber.

Abstract: A process is provided for determining the concentration of a gas in a molten metal by a carrier gas, which can be pumped to at least one analyzer, either in direct route for calibration, or for measuring through a measuring circuit with a measuring probe immersed in the molten metal, wherein the carrier gas effects a gas exchange with the molten metal, and this gas mixture is pumped to the analyzer for measurement. In order to obtain an accurate and quick reading of the concentration of a gas in a molten metal, the carrier gas is pumped for one segment of a measuring cycle directly to the analyzer for calibration, as well as to the measuring circuit for purging and for uptake of the gas to be measured, so that the gas to be measured is ready for the analyzer.

Abstract: A sampler for molten metal has a flat sample chamber arranged in a carrier tube, an inlet duct with an inflow opening arranged on the side of the flat sample chamber facing away from the immersion end of the carrier tube, and a wall surface which forms a sample analysis surface running parallel to the axis of the carrier tube. In order to create a sampler with which high-quality flat samples can be obtained and which can be easily removed from the sampler, a prechamber is arranged inside the carrier tube, at the end of the inlet duct facing away from the immersion end of the carrier tube, above the flat sample chamber and between the inlet duct and the inflow opening.

Abstract: An immersion probe includes an elongated probe body having an axis, an external surface and a first end for immersion into a bath of molten metal, the molten metal bath having a slag layer on the upper surface thereof. The first end of the probe body includes a device for detecting a characteristic of the molten metal. The immersion probe further includes a chill member movably supported by and at least partially surrounding a portion of the external surface of the probe body. The chill member is freely axially movable with respect to the probe body. A buoyancy member engages the chill member. The buoyancy member has a density such that upon immersion of the first end of the probe into the molten metal bath the chill member moves axially with respect to the probe body so that the chill member is positioned within the slag layer for chilling and collecting a slag sample. One or more stop members may be provided on the probe body for limiting movement of the chill member.

Abstract: Immersion samplers for the molten metals have a tubular sample chamber made of quartz glass or another refractory material with an inlet opening on the one end and an end, lying opposite to the inlet opening, which is mounted in a cardboard tube. An immersion sampler with a simple construction which makes possible sampling at low metal inlet velocity while preventing the formation of pinholes and pores in the sample, comprises an inlet opening for filling the sample chamber exclusively by ferrostatic pressure, the inlet having an open cross-sectional area compared to the cross-sectional area of the sample chamber directly behind the inlet opening, looking counter to the immersion direction, which is so sized that the filling velocity of the sample chamber based on ferrostatic pressure is at a maximum one fifth of the filling velocity at an inlet opening corresponding to the cross sectional area of the sample chamber directly behind the inlet opening.

Abstract: A sampler for molten metal has a carrier body, in which a sample chamber and a prechamber, connected to the latter in a sealed manner via an inflow opening, are arranged one behind the other along the axis of the carrier body, the prechamber having an inlet duct passing through the carrier body. In order to provide a sampler that can be assembled easily and reliably, even with larger manufacturing tolerances, and that allows easy removal of the sample after sampling, the sample chamber is held axially against the prechamber by means of a spring element.

Abstract: Apparatus for measuring temperatures in molten metals are known with a thermocouple arranged in a closed-end ceramic tube, wherein the junction of the thermocouple is located near the closed end of the tube, and with an outer protective casing which surrounds the closed-end tube and forms an annulus between the closed-end tube and the inner surface of the protective casing, the protective casing being substantially refractory metal oxide and graphite. To create a temperature measuring apparatus in which the thermocouple is protected by simple means from chemical destruction and thereby increases the life expectancy of the thermocouple, the annulus is substantially filled with a metal oxide powder and an oxygen-reducing means, the proportion of the oxygen-reducing means being approximately 5% by volume to approximately 95% by volume.

Abstract: An immersion sensor for molten metals has an electrically conducting support pin, whose one end is mounted in a refractory mounting material, and whose other free end has a first coating of a reference material and on top of this a second coating of a solid electrolyte material. The support pin has a third coating of a refractory material in the area of its mounted end, and this third coating on the one side extends into the mounting material, and on the other side extends into the solid electrolyte material. In order to obtain a quick reading and a stable EMF-value, the solid electrolyte material covers at least the end area of refractory coating nearest the free end of the support pin. A process for the manufacture of an intermediate for the immersion sensor applies the various coating materials of the immersion sensor in the order given above.

Abstract: The present invention is a device for measuring the temperature of a molten metal. The device includes a thermocouple element, a housing consisting of a heat-resistant material and a retainer member for receiving the thermocouple element. The retainer member has an open end and a closed end. The thermocouple element has a hot junction located proximate the closed end of the retainer member. The retainer member is positioned within the housing and is smaller in size than the housing to define a cavity therebetween. The cavity is substantially filled by a protective material which includes a metal oxide component and an oxygen reducing component.

Abstract: Two metallic half dishes are fitted together to form a sample container arranged in the hollow space of a carrying tube. The sample container serves to withdraw samples from molten metals. The hollow space surrounding the sample container is filled with granules made of a refractory material, such as corundum. The hollow space is preferably bordered on its sides by a cardboard tube, which is inserted into the carrying tube.

Abstract: Sampling devices for molten metal are known that consist of at least two cup-shaped, metallic components, which are arranged in such a way that their front (mating) surfaces face each other. These components form a sampling chamber, and they have an inlet pipe extending into the chamber. In order to construct a sampling device in a way that makes it quick and easy to remove the sample after the fluid metal has solidified, the chamber is coated with a wear-resistant layer which is temperature-stable up to approximately 1700.degree. C. This layer should be applied at least in the area of the orifice and the wall area opposite the orifice. The front surfaces of the cup-shaped components can remain uncoated.

Abstract: A device to determine phase transitions by means of thermal analysis using a sample taken from molten metal comprises an expendable measuring probe with a solidification chamber into which the molten metal flows, whereby the solidification chamber contains a thermocouple with which the course of cooling is recorded over a specific time period. According to the invention, the side walls of the solidification chamber 3 comprise a metal casing 4 that completely surrounds the chamber and extends lengthwise of the measuring probe 1. Both open ends of the casing 4 are covered by plugs 5,6 made of a material whose heat conductivity is substantially less than that of the casing material. The casing is completely surrounded by a covering 2,8 which is made of a material whose heat conductivity is substantially less than that of the metal casing. The supply orifice for the molten metal comprises a quartz pipe 9 surrounded by a metal pipe 10.