Evaluating a Ceramic Resin-Coated Sand for Aluminum and Iron Castings
Shell molding technology remains an important part of metal casting technology because it permits precision sand castings. However, there is a lack of information available on shell resin-coated sand (RCS) produced with ceramics. This paper relates the physical, mechanical, and thermo-mechanical properties of disc-shaped shell core specimens made from either silica or ceramic sands. Gravity-filled disc-shaped shell core specimens were fabricated with silica and ceramic sands. Specimens were laboratory tested and evaluated in aluminum and iron casting trials. Testing included density, abrasion, thermal distortion, hot permeability, impact and retained strength. All tests were accomplished according to newly adopted American Foundry Society standards. With a ceramic RCS, it is possible to produce cores and molds having superior abrasion resistance, strength, and thermal stability when compared to a silica RCS. Ceramic RCS shell core specimens showed fewer casting surface issues when compared to silica RCS shell core specimens in aluminum and iron casting trials.
Keywordschemically bonded sand core binder system disc-shaped specimen hot-box shell thermal distortion
The author gratefully acknowledges the technical support from P. Patel, M. Ravel and D. Moradhinazad, all graduate students from the Metal Casting Laboratory at Western Michigan University.
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