Carbon-Sulfur (C/S) Analysis

Carbon-sulfur (C/S) analysis is performed to determine the carbon and sulfur ratio in a metal sample. Elemental analysis of carbon and sulfur consists of determining the chemical composition of a sample, specifically its content. Elemental analysis makes it possible to obtain quantitative (concentration and dosage) or qualitative (presence or absence) information about chemical elements.

The high-precision equipment used in advanced laboratories to perform the dosage and elemental analysis of carbon and sulfur is equipped with an induction furnace that allows the samples to burn at high temperatures. Sulfur and carbon amounts are detected using infrared cells. These dosages are important to determine or verify the expected nuances. These elements, usually in small amounts, are necessary to evaluate the quality of metallic materials. This equipment allows identifying nuances or understanding the causes of a failure.

Carbon or oxygen levels can have a significant impact on materials and finished products. In this regard, it is recommended to perform carbon-sulfur (C/S) analysis as part of regular quality control.

When performing this analysis, the sample is melted in the induction furnace of the carbon-sulfur analyzer in an atmosphere of pure oxygen, causing sulfur to react with sulfur dioxide and carbon to react with a mixture of carbon monoxide and carbon dioxide. The elemental analyzer measures the concentration of carbon and sulfur in predominantly inorganic samples by combustion in an induction furnace and subsequent analysis of the gaseous combustion products carbon dioxide and sulfur dioxide. The high temperature of over 2000 degrees ensures complete decomposition of the sample and therefore reliable and accurate elemental analysis over a wide concentration range.

The following international standards are mainly taken into account in these analyses:

• "ASTM E1019-18 Standard test methods for the determination of carbon, sulfur, nitrogen and oxygen in steel, iron, nickel and cobalt alloys by various combustion and inert gas fusion techniques" standard developed by the American Society for Testing and Materials (ASTM). This standard describes test methods for the chemical analysis of metals and alloys. It is primarily intended to test such materials for compliance with composition specifications. These test methods cover the determination of carbon, sulfur, nitrogen and oxygen in steel, iron, nickel and cobalt alloys with chemical compositions within certain limits.
• “ISO 15350 Steel and iron - Determination of total carbon and sulfur content - Infrared absorption method after combustion in induction furnace (routine method)” standard developed by the German Institute for Standardization (DIN) and republished by the International Organization for Standardization (ISO). This standard describes an infrared absorption method for determining the total carbon and sulfur content in steel and iron after combustion in an induction furnace. This method is applicable to the carbon content of the mass fraction between 0,005-4,3 percent and the sulfur content of the mass fraction between 0,0005-0,33 percent. This method is used in single element mode, i.e., independent determination of carbon and sulfur, or in simultaneous mode, i.e., simultaneous determination of carbon and sulfur.

These standards meet and exceed the requirements of all common standards for carbon and sulfur measurement. Carbon and sulfur concentrations are closely monitored due to their impact on material properties, and it is important to determine carbon and sulfur content quickly and efficiently. Different methods are applied to measure carbon-sulfur (C/S) concentrations in steel, iron-based products or typical foundry products such as ferrochrome. Among these, multi-element techniques such as spectrometry or special carbon-sulfur analysis are common. However, modern combustion analyzers determine carbon and sulfur concentrations in a very short time. Some analyzers require only 40 seconds of analysis time to measure both carbon and sulfur. For reliable, fast elemental analysis, these instruments use a power-controllable induction furnace with intelligent lance management, a heated dust collector and an integrated catalyst. Infrared cells provide a wide measurement range. These devices allow measurement of carbon and sulfur content from a few ppm to the percentage range and are compliant with all international standards.

Among the numerous testing, measurement, analysis and evaluation studies it provides for businesses in various sectors, our organization also provides carbon-sulfur (C/S) analysis services with its trained and expert staff and advanced technological equipment.