High gas-permeability mold core molding sand and preparation method thereof

Abstract

The invention relates to high gas-permeability mold core molding sand, which is prepared from the following raw materials by weight: 5-8 parts of silicon carbide fibers, 8-10 parts of potassium feldspar, 2-3 parts of carboxymethyl cellulose, 1-2 parts of polyethylene ethyl acetate, 3-4 parts of manganese oxide, 4-5 parts of a polyamide-imide resin, 200-220 parts of clay, 2-3 parts of sodium fluorosilicate, 1-2 parts of sodium disilicate, 10-15 parts of phosphorite powder, a proper amount of water, and 20-30 parts of an auxiliary agent. According to the high gas-permeability mold core molding sand of the present invention, the molding sand is granular and has characteristics of excellent gas permeability, excellent fluidity, excellent dispersion, low moisture absorption, good collapsibility, easy removing, and recycling; the auxiliary agent of the present invention adopts alumina and other high temperature resistance materials, such that the auxiliary agent can not melt during casting, the adhesion of the clay particles can be prevented, and the recycling is easily performed; the clay is wrapped on the surface, and the binding force with the clay particles is strong, such that the molding sand plasticity is increased; the fluidity of the auxiliary agent is good; the carbon fibers are adopted so as to increase the strength and the heat resistance of the molding sand; and the high gas-permeability mold core molding sand of the present invention is suitable for mold core production.

Description

technical field [0001] The invention relates to the field of casting, in particular to a high-permeability core sand and a preparation method thereof. Background technique [0002] At present, molding sand is generally formed by mixing molding materials such as raw sand for casting, molding sand binder and auxiliary additives in a certain proportion. If the particle size of the molding sand is too large, although the air permeability is good, the surface of the casting is relatively rough and the finish is not good; if the particle size of the molding sand is too small, the air permeability of the sand mold is not good, and the aluminum casting has pores. Therefore, it is necessary to control the particle size of the molding sand. [0003] Natural clay-containing silica sand can also be used for molding sand. Coal powder clay green sand widely used at home and abroad is generally made of raw sand, binder, coal powder additives, etc. mixed with water, which has a certain ant...

AI Technical Summary

Problems solved by technology

[0003] Natural clay-containing silica sand can also be used for molding sand. Coal powder clay green sand widely used at home and abroad is generally made of raw sand, binder, coal powder additives, etc. mixed with water, which has a certain anti-sticking sand effect and material The advantages of low cost and high production efficiency, but its consumption is large, the emission is serious, and the combustion and decomposition of pulverized coal in the casting process will produce toxic gas pollution

Traditional clay molding sand is not easy to recycle, and there are still some shortcomings such as easy sand bean, poor collapsibility, poor fluidity, and poor heat resistance, which need to be improved