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 process for the on-line characterization of a surface in motion, preferably a galvannealed sheet, essentially comprises an industrial microscope associated with a stroboscopic laser illumination device, a positioning assembly, an assembly for acquiring and processing images. The obtained view fields vary between 125 ?m and 2000 ?m in width, the spatial resolution is at least 0.5 ?m, and the focussing of the system is precise to a micrometer. The images are taken on a product moving at a speed of between 1 m/s and 20 m/s and are frozen by the use of a stroboscopic illumination device with a duration of illumination of at least 10 ns. The obtained images are processed in several steps. A background average level is first of all regularly evaluated in order to be eliminated from each current image. The processed image is then divided into several zones. The sharpness of each zone is evaluated and stored in memory.

Abstract: The process for the on-line characterisation of a surface in motion, preferably a galvannealed sheet, essentially comprises an industrial microscope associated with a stroboscopic laser illumination device, a positioning assembly, an assembly for acquiring and processing images. The obtained view fields vary between 125 &mgr;m and 2000 &mgr;m in width, the spatial resolution is at least 0.5 &mgr;m, and the focussing of the system is precise to a micrometer. The images are taken on a product moving at a speed of between 1 m/s and 20 m/s and are frozen by the use of a stroboscopic illumination device with a duration of illumination of at least 10 ns. The obtained images are processed in several steps. A background average level is first of all regularly evaluated in order to be eliminated from each current image. The processed image is then divided into several zones. The sharpness of each zone is evaluated and stored in memory.