P1E-3 Ultrasonic QNDE Instrument for Quantitative Inclusion and Pore Characterization of Steel Billets

Steel fabrication suffers from inclusions and pores that are formed into steel during production. Ultrasonic characterization of unrolled steel bars is challenging due to low signal-to-noise ratio (SNR). Signal processing provides methods to characterize granular steel samples. We are developing a 9.5 MHz instrument for quantitative inclusion (manganese-sulphur) and pore characterization in immersed steel billets. The instrument is capable of quantitative foreign body classification. MnS inclusions and soft inclusions (pores) can be segregated. After the samples were characterized ultrasonically, inclusions were cut out and a scanning electron microscope (SEM) was used to validate the results. The instrumentation will allow nondestructive waste product content estimation for each waste material separately. It improves the steel fabrication quality control by giving detailed information of the inner structure and therefore allowing more precise fabrication process control.