CN104525845A - Molding sand for machine-modeling machine tool casting and preparation method thereof - Google Patents

Abstract

Molding sand for machine-modeling machine tool casting is prepared from the following raw materials in parts by weight: 1-1.5 parts of ascorbic acid, 3-6 parts of aluminum borate nano micro-particles, 20-25 parts of an expanded vermiculite powder, 10-13 parts of volcano tuff, 3-4 parts of anhydrous calcium sulfate, 1-1.3 parts of epoxidized soybean oil, 4-5 parts of a gleditsia sinensis powder, 180-200 parts of clay, a proper amount of water, and 20-30 parts of an auxiliary agent. With adopting the clay and the expanded vermiculite powder for sintering granulation, the molding sand is good in air permeability, good in dispersion and good in heat resistance, and can be recycled; through the use of the gleditsia sinensis powder and volcanic tuff, the molding sand is good in plasticity, high in modeling accuracy, and high in wet tensile strength; through the addition of the ascorbic acid, molten iron oxidation can be prevented, and high temperature collapsibility is increased; and the molding sand is suitable for the machine-modeling machine tool casting.

Description

A kind of machine molding lathe moulding sand for casting and preparation method thereof

Technical field

The present invention relates to casting field, particularly relate to a kind of machine molding lathe moulding sand for casting and preparation method thereof.

Background technology

There is particle size problem rambunctious in current molding sand, affects yield rate and the Modeling precision of foundry goods.Further, lack special molding sand for different types of foundry goods, make casting accuracy not high, yield rate is low.

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.

Above shortcoming needs to improve.

Summary of the invention

The object of the present invention is to provide a kind of machine molding lathe moulding sand for casting and preparation method thereof, this sand permeability is good, good dispersion, good heat resistance, and plasticity is good, and Modeling precision is high, and green tensile strength is high, can prevent molten iron oxidation.

Technical scheme of the present invention is as follows:

A kind of machine molding lathe moulding sand for casting, is characterized in that being made up of the raw material of following weight portion: ascorbic acid 1-1.5, aluminium borate nanoparticle 3-6, expanded vermiculite powder 20-25, volcanic tuff 10-13, dead plaster 3-4, epoxidized soybean oil 1-1.3, Chinese honey locust powder 4-5, clay 180-200, water are appropriate, auxiliary agent 20-30;

Described auxiliary agent is made up of the raw material of following weight portion: chromite sand 6-8, ceramic sand 4-5, walnut sand 2-3, aluminium oxide 3-4, silica 4-5, nice foundry sand 5-7, clay 2-3, silane coupler kh-550 0.5-1, magnesia 0.4-0.7; Preparation method is: carry out ball milling by after aluminium oxide, magnesia, silica mixing, cross 200 mesh sieves, 2-2.5 hour is calcined at 1400-1500 DEG C, add Quench in cold water, then be ground into the particle that particle diameter is less than 2mm, add chromite sand, walnut sand, grinding 30-40 minute, add other residual components, grinding 20-30 minute, to obtain final product.

The preparation method of described machine molding lathe moulding sand for casting, is characterized in that comprising the following steps:

(1) by clay, expanded vermiculite powder, dead plaster mixing, pulverize, cross 50 mesh sieves, add aluminium borate nanoparticle, the water adding 7-9% weight portion again stirs, granulation, and particle diameter is at 0.05-2.5mm, send in calcining furnace, pre-burning 20-25 minute at 300-400 DEG C, then sinters at 900-940 DEG C, takes out, polishing, to surface roughness≤0.1mm, obtains clay particle;

(2) by Chinese honey locust powder, volcanic tuff mixing, add the water of 15-18 weight portion, wet-milling 20-25 minute, dry, pulverize and obtain powder;

(3) powder that described clay particle, (2) step obtain is mixed with other residual components, then add the water mixing 8-13 minute of 3.8-4.5% weight portion, to obtain final product.

Beneficial effect of the present invention

Molding sand of the present invention is by using clay, expanded vermiculite powder, and sinter granulation, good permeability, good dispersion, good heat resistance, can recycle; By using Chinese honey locust powder, volcanic tuff, make molding sand plasticity good, Modeling precision is high, and green tensile strength is high; By adding ascorbic acid, can molten iron oxidation be prevented, increasing high temperature collapsibility performance; Molding sand of the present invention is applicable to the casting of machine molding lathe.Auxiliary agent of the present invention is high temperature resistant, good dispersion, and lubricity is good, good with the affinity of clay particle, can increase the plasticity of molding sand, gas permeability, mobility, heat resistance, prevent clay particle from boning, and improves the yield rate of foundry goods.

Detailed description of the invention

A kind of machine molding lathe moulding sand for casting, is made up of the raw material of following weight portion (kilogram): ascorbic acid 1.3, aluminium borate nanoparticle 4, expanded vermiculite powder 23, volcanic tuff 12, dead plaster 3.4, epoxidized soybean oil 1.2, Chinese honey locust powder 4.5, clay 190, water are appropriate, auxiliary agent 25;

Described auxiliary agent is made up of the raw material of following weight portion (kilogram): chromite sand 7, ceramic sand 4.5, walnut sand 2.5, aluminium oxide 3.5, silica 4.5, nice foundry sand 6, clay 2.5, silane coupler kh-550 0.7, magnesia 0.6; Preparation method is: carry out ball milling by after aluminium oxide, magnesia, silica mixing, cross 200 mesh sieves, calcine 2.3 hours at 1450 DEG C, add Quench in cold water, then be ground into the particle that particle diameter is less than 2mm, add chromite sand, walnut sand, grind 35 minutes, add other residual components, grind 25 minutes, to obtain final product.

The preparation method of described machine molding lathe moulding sand for casting, comprises the following steps:

(1) by clay, expanded vermiculite powder, dead plaster mixing, pulverize, cross 50 mesh sieves, add aluminium borate nanoparticle, the water adding 8% weight portion again stirs, granulation, and particle diameter is at 0.05-2.5mm, send in calcining furnace, pre-burning 23 minutes at 350 DEG C, then sinters at 920 DEG C, takes out, polishing, to surface roughness≤0.1mm, obtains clay particle;

(2) by Chinese honey locust powder, volcanic tuff mixing, add the water of 16 weight portions, wet-milling 23 minutes, dry, pulverize and obtain powder;

(3) powder that described clay particle, (2) step obtain is mixed with other residual components, then the water adding 4.1% 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 80KPa, gas permeability 115, and green tensile strength is 2.5KPa.

Claims (2)

1. a machine molding lathe moulding sand for casting, is characterized in that being made up of the raw material of following weight portion: ascorbic acid 1-1.5, aluminium borate nanoparticle 3-6, expanded vermiculite powder 20-25, volcanic tuff 10-13, dead plaster 3-4, epoxidized soybean oil 1-1.3, Chinese honey locust powder 4-5, clay 180-200, water are appropriate, auxiliary agent 20-30;

Described auxiliary agent is made up of the raw material of following weight portion: chromite sand 6-8, ceramic sand 4-5, walnut sand 2-3, aluminium oxide 3-4, silica 4-5, nice foundry sand 5-7, clay 2-3, silane coupler kh-550 0.5-1, magnesia 0.4-0.7; Preparation method is: carry out ball milling by after aluminium oxide, magnesia, silica mixing, cross 200 mesh sieves, 2-2.5 hour is calcined at 1400-1500 DEG C, add Quench in cold water, then be ground into the particle that particle diameter is less than 2mm, add chromite sand, walnut sand, grinding 30-40 minute, add other residual components, grinding 20-30 minute, to obtain final product.

2. the preparation method of machine molding lathe moulding sand for casting according to claim 1, is characterized in that comprising the following steps:

(1) by clay, expanded vermiculite powder, dead plaster mixing, pulverize, cross 50 mesh sieves, add aluminium borate nanoparticle, the water adding 7-9% weight portion again stirs, granulation, and particle diameter is at 0.05-2.5mm, send in calcining furnace, pre-burning 20-25 minute at 300-400 DEG C, then sinters at 900-940 DEG C, takes out, polishing, to surface roughness≤0.1mm, obtains clay particle;

(2) by Chinese honey locust powder, volcanic tuff mixing, add the water of 15-18 weight portion, wet-milling 20-25 minute, dry, pulverize and obtain powder;

(3) powder that described clay particle, (2) step obtain is mixed with other residual components, then add the water mixing 8-13 minute of 3.8-4.5% weight portion, to obtain final product.