CN104525835A - Molding sand for conformal high pressure modeling and preparation method thereof - Google Patents

Abstract

Molding sand for conformal high pressure modeling is prepared from the following raw materials in parts by weight: 2-3 parts of microcrystalline wax, 4-7 parts of nano pottery clay, 1-2 parts of a polyamide wax micro-powder, 9-12 parts of sodium-based bentonite, 7-9 parts of pulverized coal, 40-50 parts of high-potassium sand, 40-50 parts of potassium sodium stone, 20-26 parts of wollastonite, 130-160 parts of clay, an appropriate amount of water, and 20-30 parts of an auxiliary agent. Through adopting the clay for sintering granulation, the molding sand has good air permeability and good dispersion and can be recycled; through the use of the high-potassium sand, the potassium sodium stone and the nano pottery clay and through melt granulation, the heat resistance, dispersion, air permeability and compressive strength of the molding sand are increased, and bonding of clay particles can be effectively prevented; and the molding sand is high in bonding strength, and suitable for conformal high pressure modeling and casting of spheroidal graphite cast iron rear axles, chassises and the like.

Description

A kind of conformal high pressure moulding molding sand and preparation method thereof

Technical field

The present invention relates to casting field, particularly relate to a kind of conformal high pressure moulding molding sand and preparation method thereof.

Background technology

There is particle size problem rambunctious in current molding sand, if molding sand particle diameter is too large, although gas permeability is better, cast(ing) surface is more coarse, and fineness is bad; If molding sand material footpath is too little, cause mo ld void bad, foundry goods has pore to produce.Also there is the problem of poor fluidity, easily dusting beans in current molding sand.

Conventional clay molding sand has many good qualities, but exists not easy to be recycled, and poor air permeability, mobility are bad, dispersiveness is bad, collapsibility is poor, it is bad to dispel the heat, environmental pollution is serious shortcoming.

Conformal high pressure moulding molding sand requires higher green compression strength, fine air permeability, good plasticity, and common sand is difficult to reach this requirement, or defect rate is high.

Therefore, the above shortcoming that molding sand exists needs to overcome.

Summary of the invention

The object of the present invention is to provide a kind of conformal high pressure moulding molding sand and preparation method thereof, this molding sand heat resistance, dispersiveness, good permeability, compressive resistance is high, can effectively prevent clay particle from boning, be applicable to conformal high pressure moulding, casting magnesium iron back axle, chassis etc.

Technical scheme of the present invention is as follows:

A kind of conformal high pressure moulding molding sand, is characterized in that being made up of the raw material of following weight portion: microwax 2-3, nanoclay 4-7, polyamide wax micropowder 1-2, sodium bentonite 9-12, coal dust 7-9, high potassium sand 40-50, potassium sodium stone 40-50, wollastonite 20-26, clay 130-160, water are appropriate, auxiliary agent 20-30;

Described auxiliary agent is made up of the raw material of following weight portion: quartz sand 15-18, iron oxide 2-3, aluminium oxide 3-5, calcium oxide 1-1.5, talcum 3-4, rice hull ash 0.5-0.8, graphite powder 1.6-2, furfuryl alcohol resin 0.8-1.1, benzene sulfonic acid 0.5-0.7, water 1.8-2.2; Preparation method is: by quartz sand, iron oxide, aluminium oxide, calcium oxide, talcum mixing, carry out ball milling, cross 150 mesh sieves, be fired into particle with Verneuil method, particle diameter is at 0.1-2mm; Rice hull ash, graphite powder, furfuryl alcohol resin, water are mixed, add other residual components, stir, add described particle, grinding 15-20 minute, dries, and pulverize, particle diameter, at 0.5-2.5mm, to obtain final product.

The preparation method of described conformal high pressure moulding molding sand, is characterized in that comprising the following steps:

(1) by clay, wollastonite mixing, pulverize, cross 50 mesh sieves, the water adding 7-9% weight portion stirs, granulation, particle diameter, at 0.05-2.5mm, is sent in calcining furnace, pre-burning 20-25 minute at 300-400 DEG C, then sinter at 900-940 DEG C, take out, polish to surface roughness≤0.1mm, obtain clay particle;

(2) high potassium sand, potassium sodium stone are pulverized, add nanoclay and mix, make the particle of particle diameter at 0.5-2mm with Verneuil method;

(3) particle that described clay particle, (2) step obtain is mixed with other residual components, then add the water mixing 8-13 minute of 5-5.5% weight portion, to obtain final product.

Beneficial effect of the present invention

Molding sand of the present invention is by using vitrified bond granulation, and good permeability, good dispersion, can recycle; By using high potassium sand, potassium sodium stone, nanoclay, granulating through fusion method, adding the heat resistance of molding sand, dispersiveness, gas permeability and compressive resistance, can effectively prevent clay particle from boning; Molding sand adhesion strength of the present invention is high, is applicable to conformal high pressure moulding, casting magnesium iron back axle, chassis etc.Auxiliary agent of the present invention can be high temperature resistant, prevents clay particle from boning, make sand fluidity good, good permeability simultaneously, by using rice hull ash, graphite powder, the plasticity can improving molding sand and high temperature collapsibility.

Detailed description of the invention

A kind of conformal high pressure moulding molding sand, is made up of the raw material of following weight portion (kilogram): microwax 2.5, nanoclay 6, polyamide wax micropowder 1.5, sodium bentonite 11, coal dust 8, high potassium sand 45, potassium sodium stone 45, wollastonite 23, clay 140, water are appropriate, auxiliary agent 25;

Described auxiliary agent is made up of the raw material of following weight portion (kilogram): quartz sand 17, iron oxide 2.5, aluminium oxide 4, calcium oxide 1.3, talcum 3.5, rice hull ash 0.7, graphite powder 1.8, furfuryl alcohol resin 0.9, benzene sulfonic acid 0.6, water 2; Preparation method is: by quartz sand, iron oxide, aluminium oxide, calcium oxide, talcum mixing, carry out ball milling, cross 150 mesh sieves, be fired into particle with Verneuil method, particle diameter is at 0.1-2mm; Rice hull ash, graphite powder, furfuryl alcohol resin, water are mixed, add other residual components, stir, add described particle, grind 18 minutes, dry, pulverize, particle diameter, at 0.5-2.5mm, to obtain final product.

The preparation method of described conformal high pressure moulding molding sand, comprises the following steps:

(1) by clay, wollastonite mixing, pulverize, cross 50 mesh sieves, the water adding 8% weight portion stirs, granulation, particle diameter, at 0.05-2.5mm, is sent in calcining furnace, pre-burning 24 minutes at 350 DEG C, then sinter at 930 DEG C, take out, polish to surface roughness≤0.1mm, obtain clay particle;

(2) high potassium sand, potassium sodium stone are pulverized, add nanoclay and mix, make the particle of particle diameter at 0.5-2mm with Verneuil method;

(3) particle that described clay particle, (2) step obtain is mixed with other residual components, then the water adding 5.3% weight portion mixes 11 minutes, to obtain final product.

The sand test data that the present embodiment obtains are as follows: green compression strength is 124KPa, gas permeability 117, and hot green tensile strength is 2.1KPa, and normal temperature green tensile strength is 28KPa, compact rate of molding 45%.

Claims (2)

1. a conformal high pressure moulding molding sand, is characterized in that being made up of the raw material of following weight portion: microwax 2-3, nanoclay 4-7, polyamide wax micropowder 1-2, sodium bentonite 9-12, coal dust 7-9, high potassium sand 40-50, potassium sodium stone 40-50, wollastonite 20-26, clay 130-160, water are appropriate, auxiliary agent 20-30;

Described auxiliary agent is made up of the raw material of following weight portion: quartz sand 15-18, iron oxide 2-3, aluminium oxide 3-5, calcium oxide 1-1.5, talcum 3-4, rice hull ash 0.5-0.8, graphite powder 1.6-2, furfuryl alcohol resin 0.8-1.1, benzene sulfonic acid 0.5-0.7, water 1.8-2.2; Preparation method is: by quartz sand, iron oxide, aluminium oxide, calcium oxide, talcum mixing, carry out ball milling, cross 150 mesh sieves, be fired into particle with Verneuil method, particle diameter is at 0.1-2mm; Rice hull ash, graphite powder, furfuryl alcohol resin, water are mixed, add other residual components, stir, add described particle, grinding 15-20 minute, dries, and pulverize, particle diameter, at 0.5-2.5mm, to obtain final product.

2. the preparation method of conformal high pressure moulding molding sand according to claim 1, is characterized in that comprising the following steps:

(1) by clay, wollastonite mixing, pulverize, cross 50 mesh sieves, the water adding 7-9% weight portion stirs, granulation, particle diameter, at 0.05-2.5mm, is sent in calcining furnace, pre-burning 20-25 minute at 300-400 DEG C, then sinter at 900-940 DEG C, take out, polish to surface roughness≤0.1mm, obtain clay particle;

(2) high potassium sand, potassium sodium stone are pulverized, add nanoclay and mix, make the particle of particle diameter at 0.5-2mm with Verneuil method;

(3) particle that described clay particle, (2) step obtain is mixed with other residual components, then add the water mixing 8-13 minute of 5-5.5% weight portion, to obtain final product.