National University of Science and Technology “MISiS” (Moscow, Russia):

A. M. Belenkiy, Dr. Eng., Prof., Chair of power-efficient and resource-saving industrial technologies, e-mail: energomet@misis.ru
S. I. Chibizova, Cand. Eng., Associate Prof., Chair of power-efficient and resource-saving industrial technologies

Abinsk Electrometallurgical Worls (Abinsk, Russia):
K. R. Udalaya, quality management engineer

Method of thermoelectric power is one of the most common methods of non-destructive control. The principle of this method consists in causing the thermoelectric power in a circuit consisting of the sample and two electrodes which support a constant temperature gradient in the circuit. The thermoelectric power depends on the chemical composition of the sample. Study of the possibilities of this method has shown its applicability to the analysis of carbon and silicon in steel, cast iron and some ferro-alloys. At the same time most of the thermopower measurements were carried out by the static method to determine a single impurity in a small range of temperature diff erence — up to 300 ° C. In this paper the authors propose an approach to determine three elements at a time — C, Si and Mn in steels in a wide temperature range (from 20 to 1450 °C) based on dynamic signal measurement of the thermoelectric power of a liquid cooling sample taken from the bath of steelmaking unit or a solid sample heated to 500 °C.

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