In situ high temperature fiber-optic raman sensor for industrial applications
"Continuous casting in steel production uses specially developed oxyfluoride glasses (mold fluxes) to lubricate a mold and control the solidification of the steel in the mold. The composition of the flux impacts properties, including basicity, viscosity, and crystallization rate, all of which affect the stability of the casting process and the quality of the solidified steel. However, mold fluxes interact with steel during the casting process, resulting in flux chemistry changes that must be considered in the flux design. Currently, the chemical composition of mold flux must be determined by extracting flux samples from the mold during casting and then processing these samples offline to estimate the working chemical composition and, therefore, the expected properties of the flux. In this study, a fiber-optic Raman probe was combined with the concept of high-temperature Raman spectroscopy to perform in situ high-temperature Raman analysis. A customized external telescope was designed and embedded at the end of the Raman probe to extend the working distance of the probe from 0.8 cm to 3 cm, protecting the probe from the high-temperature environment for in situ studies. Raman spectra were successfully collected from room temperature to 1400 °C using the in situ fiber-optic Raman probe. Experimental results demonstrate that the composition-dependent Raman signal shifts can be detected at caster operating temperatures. High-temperature Raman analysis for in-line flux monitoring shows significant promise for the in-situ detection of changes in flux composition and physical properties during casting. In addition, the promising result shows that the in-situ fiber-optic Raman probe will be a revolutionary step forward for real-time high-temperature studies in materials science and many other fields"-- Abstract, p. iv
Composite materials, fiber optics, in situ high temperature monitoring, mold flux/slag, raman spectroscopy, sensors, Electrical and Computer Engineering, Engineering
Missouri University of Science and Technology
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