Surface defects are recurrent problems during Continuous Casting of steel due to the introduction of new grades that are often difficult to cast, as well as the everlasting pursuit for higher quality and improved yield. Accordingly, numerical modelling has become a ubiquitous tool to analyse the formation mechanisms of such defects. However, industrial application of simulations is often hampered by oversimplifications and omissions of important process details such as variations in material properties, specific casting practices or shortcomings regarding fundamental metallurgical concepts. The present manuscript seeks to create awareness on these issues by visiting key notions such as slag infiltration, interfacial resistance and Lubrication Index. This is done from a conceptual point of view based on industrial observations and numerical modelling experiences. The latter allows a re-formulation of outdated concepts and misconceptions regarding the influence of fluid flow, heat transfer and solidification on lubrication and defect formation. Additionally, the manuscript addresses common challenges and constraints that occur during industrial implementation of numerical models such as the lack of high-temperature material data for slags. Finally, the manuscript provides examples of improvements on product quality and process stability that can be achieved through a holistic approach which combines modelling with laboratory tests, experiences from operators and direct plant measurements.
|Number of pages||10|
|Publication status||Published - 2018|
Bibliographical noteFunding Information:
engineers and operators at SSAB; especially, Mr. Christer Nilsson, Dr. Patrik Wikström and Dr. Erik Roos for fruitful discussions and support during this work. PRL would like to thank Prof. Zushu Li for providing slag microstructure images and Dr. Paavo Hooli for providing the slag film overview in the mould. The research leading to these results has partly received funding from the Swedish Energy Agency (Energimyndigheten) project n° 37976-1. The research leading to these results has received co-funding from the European Union’s Research Programme of the Research Fund for Coal and Steel (RFCS) under the grant agreement n° [RFSR-CT-2011-00005]. This study was also partially supported by the Brain Korea 21 PLUS (BK21 PLUS) Project at the Division of the Eco-Humantronics Information Materials.
© 2018 ISIJ.
All Science Journal Classification (ASJC) codes
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys
- Materials Chemistry