Controlling process parameters by means of radiographic online determination of material properties when producing metallic strips and sheets

A device for determining the material properties of a polycrystalline product during a production or a quality control of the polycrystalline product by means of an X-ray diffraction, comprising:

• at least one X-ray source;
• at least one X-ray detector;
• and
• an X-ray mirror comprising a rotationally symmetrical support body, with a central opening and an inner circumferential surface defined by the central opening;
• wherein an X-ray generated by the at least one X-ray source can be emitted onto a surface of the polycrystalline product by means of the X-ray mirror, and a resulting diffraction image of the X-ray can be detected by the at least one X-ray detector, wherein the X-ray generated by the at least one X-ray source can be guided through the X-ray mirror,
• wherein a mirror surface is formed on the inner circumferential surface of the rotationally symmetrical support body, and the X-ray is both monochromatized and focused by the X-ray mirror in a direction of the polycrystalline product or in a direction of the polycrystalline product and the at least one X-ray detector,
• wherein the at least one X-ray detector is designed in a form of a surface detector, and
• wherein the polycrystalline product is a metallic product.