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.
Highlights
Additive manufacturing (AM) is a manufacturing technique by which digital 3D design data is used to build up a component by depositing material in layers [1]
The raw materials used were locally sourced chromite sand, imported furfural alcohol, and arylsulphonic acid from Voxeljet Ltd, the original equipment manufacturer (OEM), in order to ensure that the raw materials adhered to the OEM’s quality requirements
The pH appeared to decrease with increases in catalyst addition, indicating that more acid was introduced to the sand via coating, and that it decreased with a longer storage time because of acid evaporation as the coated sand was exposed to the environment
Summary
Additive manufacturing (AM) is a manufacturing technique by which digital 3D design data is used to build up a component by depositing material in layers [1]. Commercial technologies used in rapid sand casting include ExOne Company LLC (NASDAQ: XONE) [5] and Voxeljet AG (NASDAQ:VJET) [6]. They are becoming more prominent in the AM industry, and use 3DP technology. This process is one of the most encouraging and quickly evolving technologies, with applications across a number of industries It involves the additive layering of powdered material, such as refractory sand, whose layers are glued together using binder jetting technology to create a finished product that resembles the CAD data [7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
