Precipitation and phase transformation modelling to predict surface cracks and slab quality

Abstract

Improved numerical simulation tools provide valuable information for equipment designers and operators of continuous casting plants. In comparison to the collection and evaluation of process data, simulation models based on physical principles are able to provide a more detailed understanding of how individual process parameters can influence the production process and final product quality. One major goal of the numerical modelling of metallurgical processes is to predict the material behaviour using a proper description of production processes and their correlation to product properties and quality. Thus, the amount of expensive experimental trials can be reduced in the process of development. Later for standard production a numerical quality assessment is appropriate to reduce inspection efforts. Utilising commercial and in house made simulation software, the continuous casting process is simulated regarding thermal, mechanical, and phase transformation aspects. In a practical example, metallographic observations of strand surface defects, such as transverse corner cracks, are correlated to material history during the production process. As a result, the initiation of material failure can be localised more precisely and countermeasures can be taken with a higher chance of success compared to models that use only linear combinations of steel analysis and process parameters. The applicability of these simulation tools for computer aided quality control (CAQC) systems is discussed.