Non-metallic inclusions interpretation technique for factory expertise of metal product defects

Abstract

For various reasons defects are formed as discontinuities, which are identified by methods of nondestructive testing used by industry to evaluate the properties of materials in the conditions of mass industrial production. To determine the origin of their formation, investigations using light optical and scanning electron microscopy methods have to be made. The results of these studies are used to improve the technology at all stages of industrial production of metal products from the steelmaking process to the finished product [1–3]. Frequently, non-metallic inclusions (NMIs), including those inherited from the continuous cast billet, are the cause of the formation of discontinuities [1–2]. These inclusions can be exogenous, indigenous or mixed in origin. As a rule, the conclusion about the origin of inclusions is performed by a researcher of the testing laboratory, relying on his personal experience; therefore, all formulations of such reports reflect the individual approach of each engineer and are not universal. Such reports can only be processed manually, so they often go unclaimed, since they are not suitable for automated processing, for example, for finding patterns of defect formation and the ways to eliminate them. An objective judgment about the belonging of inclusions to the indigenous products of deoxidation and modification can be given on the basis of thermodynamic simulation of their composition [4–6]. Specialized commercial software Non-metallic inclusions interpretation technique for factory expertise of metal product defects