OPTIMISATION OF A RESIN-COATED CHROMITE SAND FOR RAPID SAND CASTING APPLICATIONS

• Neo Tshabalala Department of Engineering Metallurgy University of Johannesburg
• Kasongo Nyembwe Department of Engineering Metallurgy University of Johannesburg
• Malan Van Tonder Technology Transfer and Innovation Vaal University of Technology

DOI:

https://doi.org/10.7166/32-3-2665

Keywords:

Additive Manufacturing, Chromite Sand, Optimization, Moulds and Cores

Abstract

Applications of three-dimensional printing (3DP) to sand casting have been well-established in the last two decades. The preferred raw material is silica (quartz) sand, as it is the most readily available and cost effective sand. However, silica sand as a refractory material has some technical limitations, including high thermal linear expansion, low refractoriness, and thermal conductivity. Therefore, it is not suitable for all castings. Other refractory sand types are available, including chromite sand, which is abundantly available in South Africa. Analysis of the physical and chemical properties of in-laboratory coating of a locally available chromite sand was conducted through known metal foundry tests that provide an understanding of the quality and suitability of the use of chromite sand as a potential substitute for silica material for rapid sand-casting applications. The results of this study will inform the industry about the optimisation of parameters for the manufacturing of a resin-coated chromite sand and its use in additive manufacturing using a Voxeljet VX 1000 printer.