Abstract: A method for automated, in-line measurement of a differentiated surface cleanliness, in terms of carbon, of a continuously-moving metal sheet or strip, having a level of surface carbon pollution lower than 100 mg/m2, includes: generating a radiation beam using a source; focusing the radiation beam using a focusing device such that an energy density deposited on the metal strip or sheet is sufficient to create a plasma and generate CN radicals in the plasma if carbon and nitrogen are present; creating a nitrogen atmosphere around the plasma using a sweeping system with a flow rate that prevents any presence of oxygen from air in the plasma; analyzing light emitted by the plasma using an optical collection device, and redirecting the light toward a spectrometer or device for separating wavelengths of the emitted light; measuring an intensity of an intense vibration line of the CN radical.

Abstract: A method for electromagnetic and real-time measurement of a percentage of austenite contained in a steel strip in continuous motion during in-line manufacture or transformation thereof, by a device including the steel strip and a measuring device including at least: an alternating-current generator; a first coil supplied by the alternating-current generator, called a transmitting coil, and a second coil, called a receiving coil, the first and second coils being arranged parallel to each other or coaxial and on both sides of the steel strip, a distance between the coils being fixed and between 10 and 200 mm; a core of ferromagnetic material being a center of each coil, respectively; and at least one voltage-measuring device connected to terminals of the receiving coil, being a multimeter or an electronic acquisition system having an analog-digital converter coupled to a computer, to obtain the percentage of austenite contained in the steel strip.

Abstract: A method for automated, in-line measurement of a differentiated surface cleanliness, in terms of carbon, of a continuously-moving metal sheet or strip, having a level of surface carbon pollution lower than 100 mg/m2, includes: generating a radiation beam using a source; focusing the radiation beam using a focusing device such that an energy density deposited on the metal strip or sheet is sufficient to create a plasma and generate CN radicals in the plasma if carbon and nitrogen are present; creating a nitrogen atmosphere around the plasma using a sweeping system with a flow rate that prevents any presence of oxygen from air in the plasma; analyzing light emitted by the plasma using an optical collection device, and redirecting the light toward a spectrometer or device for separating wavelengths of the emitted light; measuring an intensity of an intense vibration line of the CN radical.

Abstract: The present invention relates to a device for electromagnetically measuring, in real time, the percentage of austenite contained in a continuously running steel strip during an in-line process for manufacturing or transforming the latter, such that the magnetic field produced by the alternating current flowing through the emitter coil (1) produces, in the steel strip (5), induced currents that generate an induced magnetic field creating, in the receiver coil (2), an electromotive force that can be measured by the voltage measurement device (4), the amplitude of this electromotive force being dependent on the voltage applied to the emitter coil and on the nature of the steel in the strip (5). The device is characterized in that the first and second coils (1, 2) are arranged in parallel to one another with a set distance between them and, in use, on either side of the steel strip (5).

Abstract: The present invention relates to an automated in-line method for measuring the surface cleanness of a continuously running metal sheet or strip, characterized by the following steps: a beam of radiation or a particle beam or a spark is focused onto the surface of the running strip, the transmitted power and the focal diameter being chosen so as to obtain a power density sufficient to create a plasma or hot spot which locally etches the metal in the form of a central zone surrounded by a peripheral oxidation ring; the characteristics of a zone encompassing said oxidized ring and possibly said central zone are analyzed by means of an optical image acquisition device and image processing; and an objective value indicative of the surface cleanness is deduced therefrom.

Abstract: The present invention relates to an automated in-line method for measuring the surface cleanness of a continuously running metal sheet or strip, characterized by the following steps: a beam of radiation or a particle beam or a spark is focused onto the surface of the running strip, the transmitted power and the focal diameter being chosen so as to obtain a power density sufficient to create a plasma or hot spot which locally etches the metal in the form of a central zone surrounded by a peripheral oxidation ring; the characteristics of a zone encompassing said oxidized ring and possibly said central zone are analyzed by means of an optical image acquisition device and image processing; and an objective value indicative of the surface cleanness is deduced therefrom.

Abstract: The surface of a rolling mill roll is coated with a coating comprising a metallic substance and is then marked by means of an intermittent laser beam. As a result, micro-craters are formed which penetrate the roll and which have rims containing components from the roll and the coating. The longevity of the roughness of the roll can thereby be enhanced.

Abstract: A light beam, e.g. from a laser, is transmitted onto the surface of a cold-rolled product such as steel strip. The light beam has a wavelength at least equal to the maximum roughness of the product surface. The reflected light energy is measured, preferably in the specular direction with respect to the incident beam; the surface roughness is deduced from that measurement. The light beam may be interrupted to provide two beams alternately incident on the same spot at different angles.