Compositionally complex ceramics as an alternative to chromium-based refractory aggregates

• Grant number: 23/00386-8
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: July 10, 2023
• End date: January 09, 2024
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Victor Carlos Pandolfelli
• Grantee: Otávio Henrique Borges
• Supervisor: Christos Aneziris
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Institution abroad: Technische Universität Bergakademie Freiberg (TU Bergakademie Freiberg), Germany
• Associated to the scholarship: 21/00114-2 - Development of advanced eco-friendly spinel-containing castables to replace chromite-based refractories, BP.DR

Abstract

Although not fully understood, the outstanding thermomechanical and molten metal corrosive resistant properties of electrofused magnesia-chromite aggregate (EMCA) led to its wide application in refractory compositions since the middle of the 20th century. Notwithstanding the performance of these refractories, the rising environmental and safety concerns have been driving the replacement of chrome-containing compositions by greener alternatives, such as MgAl2O4-based ones, but equivalent properties have not been achieved. In the associated doctoral project (21/00114-2), distinct spinel-inducing additives and sintering methods have been applied to alumina-based castables and, although their benefits to energy consumption and lead time, these conditions alone would hardly be enough to induce the same performance of the EMCA. In this internship project proposal, multiple electron-microscope-based techniques - complementary to those available at UFSCar and other partners in Brazil - will be used to bridge the gap of the mechanisms that lead to their unique features. Based on that and with the aid of thermodynamic calculations (CALPHAD), distinct compositionally-complex ceramics produced by electrofusion or flame spray will have their microstructure and some key properties evaluated, aiming at finding a design approach that can be used to support the development of novel raw-material that can better merge performance, cost and eco-friendliness. (AU)