Getting to the Core of Thin-Walled Castings

摘要

Through the addition of a sand additive/replacement to the cores, thin-walled castings with properties comparable to those with thicker walls and great weight were produced. Economic and environmental pressures continue to force metalcasting facilities to look for ways to produce castings with thinner walls and at lighter weights but with the same or better mechanical properties. However, several key requirements exist to produce thin-walled castings with good mechanical properties: the molding materials and processes must provide a high degree of dimensional accuracy to maintain specified wall thicknesses; the combination of metal chemistry, fluidity, pouring process, gating system design, venting and molding materials must allow the mold to fill completely before the onset of solidification and the occurrence of misruns; the metal must solidify and cool without the formation of carbides, centerline porosity or other micro-structural deficiencies that would impair the casting's physical properties.