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Sample Collection and Chemical Composition Analysis of Steel
Steel is a most widely used material in the 21st century, with the exception of the automotive industry and the construction industry, whose usage covers almost all aspects of modern industry and production. As an important material, steel requires precise control of its chemical composition before being put into production, in order to ensure its mechanical properties.
The accuracy of the chemical composition analysis of steel is mainly reflected in the accuracy of the sample collection and the precision of the analytical method. In order to ensure that the chemical composition analysis of steel is reliable and accurate, strict sample collection methods and precise analytical instruments must be used.
The sample collection of steel should be conducted in strict accordance with the sampling method and sampling process standards to ensure the accuracy and reliability of the test results. According to the provisions of GB 222-84, the sample collected from steel should be collected from several different parts of the steel. In the case of steel plate, the sample should be collected from the central side, the inner side, the outer side and the edge. The sample should be taken at least five times of each part and mixed uniformly before testing. In addition, the sample should be pre-treated before testing to remove surface dirt and other contaminants.
The chemical composition analysis of steel should be carried out in strict accordance with the Method of Analysis and Allowable Deviations of GB222-84. The method of analysis of the chemical composition of steel includes the methods of fusion and atomization or chemical analysis.
The method of chemical analysis is the most commonly used. In this analysis, the most accurate result can be obtained by using professional analysis equipment and physical chemical instruments. Generally, the unique characters and symbols (for example:C and S) of the chemical composition of steel are accurately detected and calculated.
The permissible deviations of the chemical composition of steel are also regulated by GB222-84. For example, the allowable deviation of carbon content in annealed steel should be controlled within 0.010% ; while that of nucleus sulphur should be controlled within 0.005%.
In conclusion, controlling the chemical composition of steel requires precise and accurate sample collection methods and analytical instruments. In addition, the chemical composition analysis of steel should be strictly carried out in accordance with the Method of Analysis and Allowable Deviations of GB222-84 in order to ensure the reliability and accuracy of the test results.
