Carbon and sulfur are the main factors that determine steel specifications and quality. Carbon with a carbon content higher than 1.70% is called cast iron, and less than 1.70% is called steel. Steel with carbon content higher than 0.60% is called high carbon steel, steel with carbon content between 0.25% and 0.60% is called medium carbon steel, steel with carbon content less than 0.25% is called low carbon steel, and carbon with less than 0.04% carbon is called industrial. Pure iron.
Carbon plays an important role in the performance of steel: as the carbon content increases, the hardness and strength of the steel increase, and the toughness and plasticity decrease. Conversely, when the carbon content decreases, the hardness and strength decrease, while the toughness and plasticity increase. Sulfur is present in steel, which deteriorates the quality of steel and reduces its mechanical properties, corrosion resistance and weldability. In particular, sulfur in steel, if it exists in the state of iron sulfide, because of its low melting point (about 1000 ° C), it will cause the phenomenon of "hot brittleness" of steel, that is, thermal deformation, cracking at high temperature, affecting the product. Quality and service life. Therefore, the lower the sulfur content in the steel, the better. Generally, the sulfur content in ordinary steel is less than 0.050%, the sulfur content in tool steel is less than 0.045%, and the sulfur content in high quality steel is less than 0.020%. In view of the important role of carbon and sulfur content in steel quality and performance, it is important to detect the carbon and sulfur content in steel, ie carbon and sulfur analysis.
The carbon-sulfur analyzer is a commonly used popular measuring instrument in the physical and chemical analysis room of the enterprise. The carbon-sulfur analyzer can quantitatively analyze the two non-metallic elements of carbon and sulfur in the metal material, and accurately measure the percentage of carbon and sulfur in the material. content. Carbon and sulfur analyzers are widely used in industries and fields such as smelting, casting, machinery, vehicles, pumps, ores, environmental protection, quality inspection, etc., and can easily and quickly carry out product testing in the stages of raw material acceptance, pre-furnace analysis and finished product inspection. The carbon-sulfur analyzer is equipped with a direct-reading spectrometer, and the oxygen-nitrogen-hydrogen analyzer can perfectly test the elements in the metal.
Infrared carbon and sulfur analyzers are classified into high-frequency infrared carbon and sulfur analyzers, tubular infrared carbon and sulfur analyzers, and arc-infrared carbon-sulfur analyzers according to different combustion methods. Currently, the mainstream of the market is high-frequency infrared carbon and sulfur analyzers and arc-infrared carbon. The sulfur analyzer, its product design principles are derived from the legal capacity of the legal requirements of the national standard carbon and acid-base titration of legal sulfur.
Infrared carbon sulfur analyzer analysis principle: carbon and sulfur in the sample are heated by high temperature heating under oxygen-rich conditions, and oxidized to carbon monoxide or carbon dioxide and sulfur dioxide gas. After being treated, the gas enters the absorption cell and absorbs the corresponding infrared radiation, utilizing the carbon dioxide in the oxygen stream and the infrared absorption spectrum of carbon monoxide and sulfur dioxide. It is forwarded by the detector as a signal, and the output is processed by a computer.
