CN103567359A - Clay green sand for high-pressure molding and preparation method thereof - Google Patents

Abstract

The invention discloses clay green sand for high-pressure molding and a preparation method thereof. The clay green sand is prepared from the following raw materials in parts by weight: 50-70 parts of zircon sand, 30-40 parts of chromite sand, 8-12 parts of bentonite, 5-10 parts of pottery, 3-6 parts of calcium sulfate crystal whiskers, 2-3 parts of calcium lignosulphonate, 1-2 parts of lauryl alcohol polyoxyethylene, 1.5-2.5 parts of polyoxyethylene, 1-2 parts of iron oxide red, 4-8 parts of stove ash slag, 3-5 parts of aluminum silicate fibers, 2-4 parts of composite powder and 5-10 parts of water. The molding sand disclosed by the invention is added with the aluminum silicate fibers and the calcium sulfate crystal whiskers, so that strength and toughness of the molding sand can be improved, damages to a sand mould during drawing are reduced; moreover, the molding sand further has good ability of preventing burnt-on sand and sand inclusion as well as low evolution rate, good gas permeability, and the like, can be used for effectively avoiding the defects such as gas pores and sand inclusion of a casting piece, and improving the production efficiency of a high-pressure molding line and the quality of the casting piece.

Description

Clay green-sand and preparation method thereof for high pressure moulding

Technical field

the present invention relates to a kind of molding sand and preparation method thereof, be specifically related to clay green-sand and preparation method thereof for a kind of high pressure moulding.

Background technology

High pressure moulding is at 7kg/cm by molding sand ³a kind of formative method of consolidation under above specific pressure.High pressure moulding and common form compare, have accurately high, the advantage such as surface quality is good, and production efficiency is high, and working condition is good of casting dimension.But when the molding sand of prior art is used for high pressure moulding, sand mold is broken damage easily, and the defects such as bleb, burning into sand increase, thereby cannot guarantee that high-pressure molding line is normally produced and the quality of foundry goods.

Summary of the invention

The object of the invention is to for the deficiencies in the prior art, provide that a kind of intensity is high, good toughness, clay green-sand and preparation method thereof for high pressure moulding that gas forming amount is low.

For achieving the above object, technical scheme of the present invention is as follows:

Use a clay green-sand, by the raw material of following weight portion, formed: zircon sand 50-70, chromite sand 30-40, bentonite 8-12, potter's clay 5-10, calcium sulfate crystal whiskers 3-6, calcium lignosulfonate 2-3, ethoxylated dodecyl alcohol 1-2, polyethylene glycol oxide 1.5-2.5, iron oxide red 1-2, boiler ash sediment 4-8, alumina silicate fibre 3-5, composite powder 2-4, water 5-10;

The preparation method of described composite powder is as follows: a, take perlite, fluorite and barite by weight 4-8:3-5:2-3, mix, pulverized 100-150 mesh sieve, then add water making beating and make the slurry that solid content is 50-60%, high speed ball milling 2-3h, spraying is dry; In b, the dried powder of spraying, add the coconut shell flour of 3-5%, the coal dust of the calcirm-fluoride of 2-3%, 1-2% and the yittrium oxide of 0.4-0.8%, 850-880 ℃ of calcining 30-40min, be warming up to again 1200-1250 ℃ of calcining 2-3h, shrend, then be placed in the hydrochloric acid solution that concentration is 15-20%, be heated to boiling speed lapping 20-30min, the sodium hydroxide solution regulator solution PH that is 10-15% by concentration is again to neutral, under 50-70 ℃ of bath temperature, stir 10-15min, filter, with distilled water, clean filter residue, dry; In powder after c, above-mentioned oven dry, add the sodium phosphate trimer of 2-3%, the jade powder of the soybean oil of the calcium stearate of 1-2%, 3-5%, 2-3% and N-(β-aminoethyl of 0.5-1%)-γ-aminopropyltrimethoxysilane, speed lapping 5-10min, dry, cross 200-300 mesh sieve.

The preparation method of clay green-sand for high pressure moulding, comprises the following steps:

(1), by zircon sand, chromite sand and boiler ash sediment co-grinding, after mistake 100-150 mesh sieve, with bentonite, potter's clay, iron oxide red, be dry mixed 3-4min;

(2) add the water of calcium sulfate crystal whiskers, alumina silicate fibre, polyethylene glycol oxide and 1/4-1/3, mix 2-3min, then add calcium lignosulfonate, ethoxylated dodecyl alcohol, composite powder and remaining water, mix 4-6min, shake out.

Beneficial effect of the present invention:

In molding sand of the present invention, added aluminium silicate fiber peacekeeping calcium sulfate crystal whiskers, can improve intensity and the toughness of molding sand, the damage of sand mold while reducing molding, and this molding sand also has the ability of good anti-scab, anti-burning into sand and low gas forming amount, good permeability etc., the defects such as bleb, burning into sand be can effectively avoid, the production efficiency of high-pressure molding line and the quality of foundry goods improved.

The specific embodiment

Use a clay green-sand, by the raw material of following weight (kg), formed: zircon sand 60, chromite sand 40, bentonite 10, potter's clay 8, calcium sulfate crystal whiskers 4, calcium lignosulfonate 2, ethoxylated dodecyl alcohol 1.5, polyethylene glycol oxide 2, iron oxide red 1, boiler ash sediment 6, alumina silicate fibre 4, composite powder 3, water 7;

The preparation method of described composite powder is as follows: a, take perlite, fluorite and barite by weight 5:5:3, mix, pulverized 150 mesh sieves, then adding water making beating, to make solid content be 60% slurry, high speed ball milling 2h, and spraying is dry; In b, the dried powder of spraying, add 4% coconut shell flour, 2% calcirm-fluoride, 1.5% coal dust and 0.6% yittrium oxide, 860 ℃ of calcining 40min, be warming up to 1230 ℃ of calcining 2h, shrend, is then placed in concentration and is 15% hydrochloric acid solution again, be heated to boiling speed lapping 25min, the sodium hydroxide solution regulator solution PH that is 10% by concentration again, to neutral, stirs 10min under 70 ℃ of bath temperatures, filters, with distilled water, clean filter residue, dry; In powder after c, above-mentioned oven dry, add 2% sodium phosphate trimer, 1.5% calcium stearate, 4% soybean oil, 2% jade powder and N-(β-aminoethyl of 0.7%)-γ-aminopropyltrimethoxysilane, speed lapping 6min, dries, and crosses 250 mesh sieves.

The preparation method of clay green-sand for high pressure moulding, comprises the following steps:

(1), by zircon sand, chromite sand and boiler ash sediment co-grinding, after mistake 150 mesh sieves, with bentonite, potter's clay, iron oxide red, be dry mixed 3min;

(2) add the water of calcium sulfate crystal whiskers, alumina silicate fibre, polyethylene glycol oxide and 1/3, mix 2min, then add calcium lignosulfonate, ethoxylated dodecyl alcohol, composite powder and remaining water, mix 5min, shake out.

The performance test of the present embodiment molding sand is as follows:

Green compression strength (kPa): 115

Green tensile strength (KPa): 31

Gas permeability: 107

Compact rate of molding (%): 39

Shatter index (%): 85.

Claims (2)

1. a high pressure moulding clay green-sand, it is characterized in that, by the raw material of following weight portion, formed: zircon sand 50-70, chromite sand 30-40, bentonite 8-12, potter's clay 5-10, calcium sulfate crystal whiskers 3-6, calcium lignosulfonate 2-3, ethoxylated dodecyl alcohol 1-2, polyethylene glycol oxide 1.5-2.5, iron oxide red 1-2, boiler ash sediment 4-8, alumina silicate fibre 3-5, composite powder 2-4, water 5-10;

The preparation method of described composite powder is as follows: a, take perlite, fluorite and barite by weight 4-8:3-5:2-3, mix, pulverized 100-150 mesh sieve, then add water making beating and make the slurry that solid content is 50-60%, high speed ball milling 2-3h, spraying is dry; In b, the dried powder of spraying, add the coconut shell flour of 3-5%, the coal dust of the calcirm-fluoride of 2-3%, 1-2% and the yittrium oxide of 0.4-0.8%, 850-880 ℃ of calcining 30-40min, be warming up to again 1200-1250 ℃ of calcining 2-3h, shrend, then be placed in the hydrochloric acid solution that concentration is 15-20%, be heated to boiling speed lapping 20-30min, the sodium hydroxide solution regulator solution PH that is 10-15% by concentration is again to neutral, under 50-70 ℃ of bath temperature, stir 10-15min, filter, with distilled water, clean filter residue, dry; In powder after c, above-mentioned oven dry, add the sodium phosphate trimer of 2-3%, the jade powder of the soybean oil of the calcium stearate of 1-2%, 3-5%, 2-3% and N-(β-aminoethyl of 0.5-1%)-γ-aminopropyltrimethoxysilane, speed lapping 5-10min, dry, cross 200-300 mesh sieve.

2. the preparation method of clay green-sand for high pressure moulding as claimed in claim 1, is characterized in that comprising the following steps:

(1), by zircon sand, chromite sand and boiler ash sediment co-grinding, after mistake 100-150 mesh sieve, with bentonite, potter's clay, iron oxide red, be dry mixed 3-4min;

(2) add the water of calcium sulfate crystal whiskers, alumina silicate fibre, polyethylene glycol oxide and 1/4-1/3, mix 2-3min, then add calcium lignosulfonate, ethoxylated dodecyl alcohol, composite powder and remaining water, mix 4-6min, shake out.