Sign In MSDS Analytical Services Careers Contact Us Logo Minteq Logo Minerals Technologies > Minteq > Specialty Minerals > OUR COMPANY PRODUCTS & MARKETS ANALYTICAL SERVICES INVESTOR RELATIONS MARKETS & INDUSTRIES ABOUT US OUR BUSINESS MINERALS & PRODUCTS MARKETS & APPLICATIONS LOCATIONS Ferrotron About Us Laser Profile Products Laser Distance and Level Measurement Immersion Measurement Probes Temperature and Oxygen Measurement Electrode Regulation Annealing Control Systems for Rolling Mills Ferrotron>Annealing Control Systems for Rolling Mills Annealing Control Systems for Rolling Mills Measuring principle Ultrasound signals reflected by metallic material. Under a certain angle a maximum signal is detected (about 31° for stainless steel). The received signal includes information on the grain size which can be compared with a calibration curve. Thus the values of the grain size can be calculated. In case of the used ultrasound frequency of 25 MHz the measuring range is about 8 to 40 mm. Typical accuracy is +/- 2 mm. Measuring principle After being cold-rolled, steel strip is annealed to achieve recrystallization. In case of ferritic stainless steel there is a clear correlation between grain structure, mechanical properties and magnetic behavior. During the annealing process the values of the apparent remanence drop significantly, reaching a minimum value in case of full recrystallization. Overannealing can be observed by increasing values because of the formation of Martensite. The measuring system consists of a magnetizing roller and a field detecting roller which are mounted over strip guiding roll. Brochure FAQ Presentation