Measurement of viscosity and melting characteristics of mould powder slags by ultrasonics

Abstract

The paper presents an attempt to find the possibility of measuring high temperature properties of mould powder slags such as viscosity, break temperature, liquidus temperature during heating as well as solidification start and solidification end temperatures during cooing using ultrasonics. These powders are used in continuous casting of steel and the abnormality in their properties can impact the productivity and quality of the steel products. These properties are in general measured by high temperature rotational viscometers, hot stage microscopes and DTA instruments. Here, the fundamental flexural guided wave mode F(1,1) in a ceramic buffer rod was employed in experiments. The results show the possibility of measuring all the above properties in single experiment by measuring ultrasonic reflection factors during continuous heating and cooling of the mould powders. The advantage of the ultrasonic system is that it can be installed in the plant for online monitoring of these properties. The ultrasonically measured properties of the mould powders supplied by five different suppliers were compared with those measured by rotational viscometers and estimated by mathematical models.

A Brief Review of Viscosity Models for Slag in Coal Gasification

“…For using the rotating crucible viscometer to measure the viscosity of blast furnace type slags, we refer the reader to Saito et al, (2003). Pandey et al (2011) presented a novel technique, whereby they attempted to measure the properties of mould powder slags, such as viscosity, liquidus temperature, etc., using ultrasonics.…”

Multi-level temperature measurements using ultrasonic waveguides

“…They also verified this technique on many different NIST standards glass samples and compared the results with high temperature rotating viscometer measurements. Pandey et al [18] used similar ultrasonic waveguides for characterizing the melts that are used for lubricating molds during the steel forming process.…”

Temperature dependent E and G measurement of materials using ultrasonic guided waves

“…Thus such methods have been extensively used for developing sensors for level, density, temperature, and rheology measurement of the surrounding fluid [1][2][3][4][5][6][7][8][9]. While using as a sensor, the material property of the waveguide (density and elastic moduli), as a function of temperature, were assumed to be known.…”