Molding sand comprising silica sand and preparing method of molding sand

The invention provides molding sand comprising silica sand and a preparing method of the molding sand and relates to the field of casting molding sand. The molding sand comprises the following raw materials including, by weight, 60-85 parts of silica sand, 40-55 parts of kaolin, 10-18 parts of boron fiber, 8-15 parts of epoxy resin, 5-10 parts of sodium stearate, 7-12 parts of dibasic lead stearate, 12-16 parts of modified polystyrene and 25-35 parts of auxiliaries. The prepared molding sand is high in strength, good in heat stability, small in gas volume and suitable for casting of various castings, and the influences to the castings are little. 本发明提供了种含硅砂的型砂及其制备方法，涉及铸造用型砂领域；它由以下重量份的原料组成：硅砂60-85份、高岭土40-55份、硼纤维10-18份、环氧树脂8-15份、硬脂酸钠5-10份、二盐基硬脂酸铅7-12份、改性聚苯乙烯12-16份、助剂25-35份；本发明制备的型砂强度高，热稳定性好，发气量小，对铸件影响小，适合多种铸件铸造。