High-refractoriness and low-expansion molding sand for steel castings and preparation method of molding sand

Abstract

The invention discloses high-refractoriness and low-expansion molding sand for steel castings and a preparation method of the molding sand. The molding sand is prepared from raw materials in parts by weight as follows: 36-48 parts of kaolin, 17-33 parts of desulfurized petroleum coke waste, 14-26 parts of lithium chinastone, 10-20 parts of sericite, 12-24 parts of aluminum ash, 41-53 parts of carborundum, 9-18 parts of hornblende, 5-10 parts of volcanic, 4-7 parts of ultrafine cobalt powder, 3-6 parts of cerium oxide hollow nanospheres, 10-15 parts of periclase, 6-12 parts of sodium carboxymethyl inulin, 5-8 parts of sodium tungstate and 490-530 parts of a modifier. The added raw materials such as the desulfurized petroleum coke waste, the aluminum ash, the ultrafine cobalt powder, the cerium oxide hollow nanospheres, periclase, sodium tungstate and the like can significantly improve the refractoriness of the molding sand and reduce the thermal expansion coefficient of the molding sand, so that the molding sand is not expanded and broken easily at the high temperature, the quality of the castings is improved, and the rejection rate of the castings is reduced.

Description

technical field [0001] The invention relates to a high refractory low-expansion molding sand for steel castings and a preparation method thereof, belonging to the technical field of molding sand. Background technique [0002] Sand casting is the most common casting method, and molding sand is the most important molding material in the current molding process. Molding sand is generally made by mixing molding materials such as raw sand for casting, molding sand binder and auxiliary additives in a certain proportion. Castings produced with sand molds account for more than 80% of the total casting production. The quality of molding sand directly affects the appearance quality of castings and casting defects such as sand holes, pores, and sand inclusions. With the continuous development of casting technology, the requirements for the performance of molding sand are getting higher and higher. The molding sand currently on the market has the disadvantages of low refractoriness an...

AI Technical Summary

Problems solved by technology

With the continuous development of casting technology, the performance requirements of molding sand are getting higher and higher. The molding sand currently on the market has the disadvantages of low refractoriness and high thermal expansion coefficient, which affects the quality of castings.