Materials Processing Fundamentals: Continuous Casting/Slag and Ladle Treatment
Sponsored by: TMS Extraction and Processing Division, TMS Materials Processing and Manufacturing Division, TMS: Process Technology and Modeling Committee
Program Organizers: Samuel Wagstaff, Oculatus Consulting; Alexandra Anderson, Gopher Resource; Adrian Sabau, Oak Ridge National Laboratory
Wednesday 8:30 AM
March 22, 2023
Room: 29B
Location: SDCC
Session Chair: Adrian Sabau, Oak Ridge National Laboratory; Alexandra Anderson, Gopher Resource
8:30 AM Introductory Comments
8:35 AM
Heat Transfer Characteristic between Ingot and Mold during an Ingot Casting Process: Yuta Shimamura1; Takanori Yoshioka1; 1Sanyo Special Steel Co.,Ltd.
It is known that the estimation of interfacial heat transfer coefficient (IHTC) between ingot and mold is difficult due to the gap formation during solidification of steel melt. This study aimed to clarify the dominant factor of the IHTC between ingot and mold to obtain a simulation technique for ingot casting process with high accuracy. By means of the inverse problem analysis for the measured temperature transition of mold, the IHTC was estimated as 300W/m2K. Thereafter, the temperature transition of mold was simulated with a FEM software ProCAST using the obtained IHTC value. The simulated temperature transition was in a good agreement with the measured one. Then, the IHTC was also estimated in a different way with considering conduction and radiation theories. The estimation result corresponded well with the one obtained through the inverse analysis. Therefore, it was clarified that the IHTC in this study is dominantly controlled by radiation.
8:55 AM
How to Prevent Porosity Defects in Steel Casting Component: Izudin Dugic1; 1Linnaeus University
The production of steel casting is often very complicated and difficult. To produce quality castings it requires the casting to be clean and free from any defects. One of the main casting defects is hot tearing, also known as a crack or shortness. This phenomenon represents the formation of an irreversible failure (crack) in the steel semisolid casting. The second defect which very often occur in casting is porosity. Porosity is often used to describe any void or hole found in a casting. To control the porosity you need to understand its sources and causes. Porosity can occur either by gas formation, solidification shrinkage, or non-metallic compound formation, all while the metal is liquid.This experimental work is focused on reducing the porosity defects on steel casting component at a production scale. The produced casting component was strongly affected by porosity defects.
9:15 AM Cancelled
A Self-adaptive Data-driven System for Online Monitoring of Castability During Continuous Casting of Steels.: Kuthe Sudhanshu1; Björn Glaser1; Roman Rössler2; Izaskun Alonso Oña3; 1KTH Royal Institute of Technology; 2Voestalpine Stahl GmbH; 3Research and Development, Sidenor
A novel online monitoring system "CHECKCAST" was developed using a self-adapted deep learning algorithm to monitor the castability of high-strength low alloyed steels in real-time. The proposed method uses steel and non-metallic inclusions compositions as inputs to forecast steel's castability in the form of signal-based output. The emphasis is given to designing robust deep learning algorithms which can later be deployed as a decision support system for online process control. Real-time industrial data was collected from the steel plant to investigate the correlation among steel and inclusion compositions with respect to castability parameters of high strength low alloyed steels. Deep feature synthesis algorithm was used on the inputs to make the system self-adaptive and auto-adjustable in case of data drift so that online monitoring of castability can be done without any hindrance. By incorporating actual industrial conditions, it was found that the proposed monitoring system helped in robust process planning.
9:35 AM
Toward Meso-scale Modelling of Slag Foaming Phenomena in Pyrometallurgy: Quinn Reynolds1; Oliver Oxtoby2; 1Mintek; 2ENGYS Ltd
In pyrometallurgical smelting dispersed multiphase flows can occur due to phase mixing between immiscible molten process materials such as slag and alloy, or decoupling of gases from one of the molten phases. The latter problem can result in slag foaming, which occurs when gas bubbles are unable to escape from the viscous slag phase rapidly enough and a low-density foam layer builds up at the surface of the slag pool. This paper will present the evaluation and application of the dynamic multi-marker (DMM) method, a novel meso-scale computational fluid dynamics algorithm for efficient modelling of dispersed phase systems, for slag foaming problems. Foaming behaviour and gas-liquid decoupling will be studied using numerical simulations of test systems, and the results will be compared to established empirical relationships. The value of DMM both as a direct simulation method and for supplementation of experimental data will be assessed and discussed.
9:55 AM Break
10:15 AM Cancelled
Effect of High FeOx Containing Material Dissolution in Hisarna Slag: Bharath Sampath Kumar1; Koen Meijer2; Zushu Li1; 1University of Warwick; 2Tata Steel EU
The HIsarna technology is a low carbon and high energy efficient alternative ironmaking process. The HIsarna off-gas contains CO2 in high concentrations, making it CCS/CCU ready. It will emit limited amount of dust; the hot metal contains low phosphorous, and this one-step approach significantly reduces capex and opex. The HIsarna pilot plant experienced sudden and uncontrolled slag foaming. Slag foaming incidents are unwanted and may disrupt the production. One theory of these foaming incidents is due to accretions containing FeOx falling in the liquid bath. High temperature laboratory experiments were done and analysed using various techniques like SEM, XRF and XRD. Slow dissolution of solid FeOx in a non-foaming HIsarna slag was observed, which is in contradiction to the sudden slag foaming. Accretion falling in the liquid bath seems not to be the main cause of slag foaming.