CN104475660A - Rare earth-containing foundry molding sand and preparation method thereof - Google Patents

Abstract

The invention relates to rare earth-containing foundry molding sand, which is prepared from the following raw materials by weight: 15-20 parts of coal gangue, 3-4 parts of vitrified micro-bead, 2-2.5 parts of calcium stearate, 220-240 parts of clay, 2-3 parts of calcium ricinate, 4-6 parts of dioctyl sebacate, 6-9 parts of diopside, 6-9 parts of limestone, 3-4 parts of rare earth, a proper amount of water, and 20-30 parts of an auxiliary agent. According to the rare earth-containing foundry molding sand of the present invention, the rare earth is used, such that the surface abrasion resistance of the cast can be increased; the molding sand has characteristics of particle shape, good gas permeability, good fluidity, good dispersion 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; and the molding sand has characteristics of high strength, good cast surface quality and high production efficiency.

Description

A kind of casting sand containing rare earth and preparation method thereof

Technical field

The present invention relates to a kind of casting field, particularly relate to a kind of casting sand containing rare earth and preparation method thereof.

Background technology

Current molding sand is generally mixed according to a certain percentage by Modeling Materials such as Foundry sand, moulding sand binder and additional things.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, aluminium casting has pore to produce.Therefore the particle diameter controlling molding sand is needed.

Molding sand also can with natural silica sand argillaceous, domestic and international widely used coal dust clay green-sand, generally formed with the water system of mixing by roughing sand, binding agent, coal dust additive etc., there is certain Sand sticking-resistant effect and the advantage that the cost of material is low, production efficiency is high, but its consumption is large, discharge seriously, at casting process coal dust firing decomposition generation toxic gas is polluted.Conventional clay molding sand is not easy to be recycled, also there is the shortcomings such as easy dusting beans, collapsibility is poor, poor fluidity, heat resistance are bad, needs to improve.

Summary of the invention

The object of the present invention is to provide a kind of casting sand containing rare earth and preparation method thereof, this molding sand can increase the surface abrasion resistance of foundry goods, good permeability, good fluidity, good dispersion, and intensity is high, and surface quality of continuous castings is good, and production efficiency is high.

Technical scheme of the present invention is as follows:

Containing the casting sand of rare earth, it is characterized in that being made up of the raw material of following weight portion: gangue 15-20, glass bead 3-4, calcium stearate 2-2.5, clay 220-240, castor oil acid calcium 2-3, di-n-octyl sebacate 4-6, diopside 6-9, lime stone 6-9, rare earth 3-4, water are appropriate, auxiliary agent 20-30;

Described auxiliary agent is made up of the raw material of following weight portion: two oleamide 0.4-0.6, Bi2O3 1-2, B2O3 1-2 of aluminium oxide 13-17, titanium dioxide 3-4, quartz sand 3-5, tall oil 0.5-1, dolomol 1-1.4, ethylene, clay 3-4, silane resin acceptor kh-550 0.8-1.2, water are appropriate; Preparation method is: by aluminium oxide, titanium dioxide, quartz sand, Bi2O3, B2O3 mixing, sends into dry pot and is heated to melt, add Quench in cold water, be ground into the particle of particle diameter≤1.5mm; Add in 4-5 weight parts water by clay, silane resin acceptor kh-550, add described particle after stirring, grinding 20-30 minute, dries, and pulverize, particle diameter at 0.05-2mm, then mixes with other residual components, stirs, to obtain final product.

The preparation method of the described casting sand containing rare earth, is characterized in that comprising the following steps:

(1) by clay, diopside, lime stone, gangue mixing, pulverize, cross 50 mesh sieves, the water adding 7-9% weight portion stirs, granulation, particle diameter, at 0.05-2mm, is sent in calcining furnace, pre-burning 20-25 minute at 300-400 DEG C, then sinter at 900-1000 DEG C, take out, polish to surface roughness≤0.1mm, obtain clay particle;

(2) get the water of 20-30 weight portion, add rare earth, stir, obtain slurry, clay particle is seethed while spray into described slurry, mix rear placement 2-3 hour, dry, obtain mixed material;

(3) material that (2) step obtains is mixed with other residual components, then the water adding 1-2% weight portion mixes, and to obtain final product.

Beneficial effect of the present invention

Molding sand of the present invention employs rare earth, can increase the surface abrasion resistance of foundry goods; This molding sand is grain shape, good permeability, good fluidity, good dispersion, but also can recycling; Auxiliary agent of the present invention employs the exotic materials such as aluminium oxide, can not be melted, clay particle can be prevented to be bonded together when casting, convenient recycling, simultaneously because Surface coating has clay, strong with the adhesion of clay particle, add the plasticity of molding sand, simultaneously the good fluidity of this auxiliary agent; This sand bond is high, and surface quality of continuous castings is good, and production efficiency is high.

Detailed description of the invention

Containing a casting sand for rare earth, be made up of the raw material of following weight portion (kilogram): gangue 18, glass bead 3.5, calcium stearate 2.3, clay 230, castor oil acid calcium 2.5, di-n-octyl sebacate 5, diopside 8, lime stone 7, rare earth 3.5, water are appropriate, auxiliary agent 25;

Described auxiliary agent is made up of the raw material of following weight portion (kilogram): the two oleamide 0.5 of aluminium oxide 15, titanium dioxide 3.5, quartz sand 4, tall oil 0.7, dolomol 1.2, ethylene, Bi2O3 1.5, B2O3 1.5, clay 3.5, silane resin acceptor kh-550 1, water are appropriate; Preparation method is: by aluminium oxide, titanium dioxide, quartz sand, Bi2O3, B2O3 mixing, sends into dry pot and is heated to melt, add Quench in cold water, be ground into the particle of particle diameter≤1.5mm; Add in 4.5 weight parts waters by clay, silane resin acceptor kh-550, add described particle after stirring, grind 25 minutes, dry, pulverize, particle diameter at 0.05-2mm, then mixes with other residual components, stirs, to obtain final product.

The preparation method of the described casting sand containing rare earth, comprises the following steps:

(1) by clay, diopside, lime stone, gangue mixing, pulverize, cross 50 mesh sieves, the water adding 8% weight portion stirs, granulation, particle diameter, at 0.05-2mm, is sent in calcining furnace, pre-burning 23 minutes at 350 DEG C, then sinter at 950 DEG C, take out, polish to surface roughness≤0.1mm, obtain clay particle;

(2) get the water of 25 weight portions, add rare earth, stir, obtain slurry, clay particle is seethed while spray into described slurry, mix rear placement 2.5 hours, dry, obtain mixed material;

(3) material that (2) step obtains is mixed with other residual components, then the water adding 1.5% weight portion mixes, and to obtain final product.

The sand test data that the present embodiment obtains are as follows: green compression strength is 180KPa, gas permeability 155, and hot green tensile strength is 4.6KPa, and normal temperature green tensile strength is 30KPa.

Claims (2)

1. containing the casting sand of rare earth, it is characterized in that being made up of the raw material of following weight portion: gangue 15-20, glass bead 3-4, calcium stearate 2-2.5, clay 220-240, castor oil acid calcium 2-3, di-n-octyl sebacate 4-6, diopside 6-9, lime stone 6-9, rare earth 3-4, water are appropriate, auxiliary agent 20-30;

Described auxiliary agent is made up of the raw material of following weight portion: two oleamide 0.4-0.6, Bi2O3 1-2, B2O3 1-2 of aluminium oxide 13-17, titanium dioxide 3-4, quartz sand 3-5, tall oil 0.5-1, dolomol 1-1.4, ethylene, clay 3-4, silane resin acceptor kh-550 0.8-1.2, water are appropriate; Preparation method is: by aluminium oxide, titanium dioxide, quartz sand, Bi2O3, B2O3 mixing, sends into dry pot and is heated to melt, add Quench in cold water, be ground into the particle of particle diameter≤1.5mm; Add in 4-5 weight parts water by clay, silane resin acceptor kh-550, add described particle after stirring, grinding 20-30 minute, dries, and pulverize, particle diameter at 0.05-2mm, then mixes with other residual components, stirs, to obtain final product.

2., according to claim 1 containing the preparation method of the casting sand of rare earth, it is characterized in that comprising the following steps:

(1) by clay, diopside, lime stone, gangue mixing, pulverize, cross 50 mesh sieves, the water adding 7-9% weight portion stirs, granulation, particle diameter, at 0.05-2mm, is sent in calcining furnace, pre-burning 20-25 minute at 300-400 DEG C, then sinter at 900-1000 DEG C, take out, polish to surface roughness≤0.1mm, obtain clay particle;

(2) get the water of 20-30 weight portion, add rare earth, stir, obtain slurry, clay particle is seethed while spray into described slurry, mix rear placement 2-3 hour, dry, obtain mixed material;

(3) material that (2) step obtains is mixed with other residual components, then the water adding 1-2% weight portion mixes, and to obtain final product.