Rapid determination of cleanliness for steel by optical emission spectrometer

Abstract

In order to inspect the quality of molten steel, a new algorithm for rapid determination of inclusion characteristics is studied. Principal factor that decides high-grade steel quality depends on size distribution of oxide inclusion or total oxygen in steel. Element composition and size distribution of inclusion can't be determined by the current method of oxide inclusion determination at the same time. A new technology for inclusion determination should be developed since the analyzing time of inclusion in steel takes a long time. To reduce the analyzing time, the technology should be based on the modified optical emission spectrometer coupled with equipment for pulse discriminator, pre-amplification, data acquisition function, and data processing. In this paper, the determination of alumina inclusion size distribution, inclusion composition, and steel cleanness are studied by the new method. The iron HIP (Hot Isostatic Pressure) samples with alumina inclusion generate pulses in the right part of Gaussian fit distribution. These pulses indicate alumina inclusion signals and the pulse intensities are related to the inclusion size are also discussed. Also, we displayed the size distribution of alumina inclusion for the steel production process samples. And the total area of the size distribution for alumina inclusion is proportioned to the cleanness of steel.