CN102836957A - Lost foam coating and preparation method thereof - Google Patents
Lost foam coating and preparation method thereof Download PDFInfo
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- CN102836957A CN102836957A CN2012103204317A CN201210320431A CN102836957A CN 102836957 A CN102836957 A CN 102836957A CN 2012103204317 A CN2012103204317 A CN 2012103204317A CN 201210320431 A CN201210320431 A CN 201210320431A CN 102836957 A CN102836957 A CN 102836957A
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Abstract
The invention relates to a lost foam coating and a preparation method thereof. The coating comprises the following components in parts by weight: 22-27 parts of quartz powder, 28-33 parts of zircon sand, 1-4 parts of bentonite, 0.5-1.5 part of water glass, 1-2.5 parts of sodium carboxy methyl cellulose, 0.2-0.5 part of n-caprylic alcohol and 0.2-0.5 part of fatty alcohol-polyoxyethylene ether. The lost foam coating provided by the invention has an excellent stripping effect and superior permeability, i.e., phenomena of air pores and slag inclusion can be effectively prevented, the quality of a casting is improved, subsequent treatment is simple, and a large amount of labor is saved.
Description
Technical field
The invention belongs to casting field, particularly lost foam cast steel manufacturing technology field.
Background technology
Lost foam casting (claiming cavityless casting again) is that the bubbles model bonding similar with the casting dimension shape is combined into model cluster; After brushing fireproof coating and oven dry; Be embedded in vibration molding in the dried quartz sand, under negative pressure, pour into a mould, make the model gasification; Liquid metals occupies modal position, solidifies the novel casting method that the cooling back forms foundry goods.
With the conventional cast compared with techniques, lost foam casting has following characteristics: 1, casting quality is good, and cost is low; 2, material is not limit, and size is all suitable; 3, dimensional accuracy is high, and any surface finish reduces the cleaning work amount; 4, internal flaw significantly reduces, dense structure; 5, can realize extensive, production in enormous quantities, can improve operating environment greatly, reduce labour intensity, reduce energy resource consumption.
Though lost foam casting process is comparatively fast developed at present, coating technology does not also reach desirable requirement.Because coating property directly influences the quality of foundry goods, coating is except isolating metal liquid contacts with the direct of molding sand, prevents that foundry goods from producing outside penetration and the chemical scab, also has an important function: formation and maintenance foundry goods die cavity.So require lost foam paint must have higher normal temperature strength and elevated temperature strength, and suitable hot permeability will be arranged.
Yet the quality of coating also has the shortcoming of each side at present, and for example in cast steel was produced, after the casting cooling, lost foam paint was not easy to peel off from foundry goods, significantly increases follow-up grinder buffing processing cost.
Summary of the invention
The objective of the invention is to propose a kind of deficiency that can overcome existing lost foam paint, have lost foam paint of superperformance and preparation method thereof.
In order to reach the object of the invention, the inventor is through coating relic analysis discovery, and the coating internal layer directly contacts with molten steel, and skin directly contacts with molding sand.During casting, high-temperature molten steel is can be with the coating internal layer wetting and immerse coating particles of aggregates gap.After treating that casting finishes, in the slow cooling procedure of foundry goods, molten steel condenses into one with coating and foundry goods, thereby makes coating be difficult to peel off from cast(ing) surface.
Learn to have only the molten steel of letting to immerse the particles of aggregates gap from above analysis, form tangible line of demarcation; Just can avoid this phenomenon; Yet because particles of aggregates can not be too little, descend otherwise can make gas permeability, the apperance gasification product can not appear smoothly; Can cause pore, slag inclusion phenomenon, make casting quality descend.
Inventor's imagination if the coating internal layer can generate the glassy phase of one deck molten condition when cast, at first is blocked between molten steel and the refractory aggregate, stops the infiltration of molten steel, should be able to play better action.
Therefore, the application adopts following formulation for coating material to solve the problems referred to above.
A kind of lost foam paint; Comprise following component: silica flour 22 ~ 27 weight portions, zircon sand 28 ~ 33 weight portions, bentonite 1 ~ 4 weight portion, waterglass 0.5 ~ 1.5 weight portion, sodium carboxymethylcellulose 1 ~ 2.5 weight portion, n-octyl alcohol 0.2 ~ 0.5 weight portion, AEO 0.2 ~ 0.5 weight portion.
In one embodiment of the invention; The proportioning of each component of lost foam paint is following: silica flour 27 weight portions, zircon sand 33 weight portions, bentonite 1 weight portion, waterglass 1.5 weight portions, sodium carboxymethylcellulose 1 weight portion, n-octyl alcohol 0.5 weight portion, AEO 0.5 weight portion.
In another embodiment of the present invention; The proportioning of each component of lost foam paint is following: silica flour 22 weight portions, zircon sand 28 weight portions, bentonite 4 weight portions, waterglass 0.5 weight portion, sodium carboxymethylcellulose 2.5 weight portions, n-octyl alcohol 0.2 weight portion, AEO 0.2 weight portion.
In another embodiment of the present invention; The proportioning of each component of lost foam paint is following: silica flour 24 weight portions, zircon sand 30 weight portions, bentonite 3 weight portions, waterglass 1.3 weight portions, sodium carboxymethylcellulose 2 weight portions, n-octyl alcohol 0.3 weight portion, AEO 0.4 weight portion.
In another embodiment of the present invention; The proportioning of each component of lost foam paint is following: silica flour 25 weight portions, zircon sand 30 weight portions, bentonite 2 weight portions, waterglass 1 weight portion, sodium carboxymethylcellulose 1.5 weight portions, n-octyl alcohol 0.3 weight portion, AEO 0.3 weight portion.
A kind of preparation method of lost foam paint comprises following steps: A. adds water with bentonite, stirs into bentonite slurry; B. silica flour, zircon sand are stirred in milling apparatus, add entry then, make that powder is moistening and stir, as aggregate; C. after waterglass, sodium carboxymethylcellulose, n-octyl alcohol and AEO being mixed, add entry, be mixed with the aqueous solution; D. the said aggregate that said bentonite slurry that steps A is made and step B make adds in the said aqueous solution that step C makes, and fully mixes.
Further, the alr mode of said steps A was specially: with the rotating speed high-speed stirred more than the 1000rpm 6 hours.
Further, the hybrid mode of said step D is specially: after 1 hour, kept the following rotating speed stirring at low speed of 600rpm 10 hours with the rotating speed high-speed stirred more than the 1000rpm.
Through adopting lost foam paint provided by the invention, have splendidly when peeling off effect, permeability is excellent.That is, can prevent pore, slag inclusion phenomenon effectively, improve the quality of foundry goods.The coating of coating is easy to peel off from cast(ing) surface, and subsequent treatment is simple, saves a large amount of manual works.
The specific embodiment
Lost foam paint of the present invention; Comprise following component: silica flour 22 ~ 27 weight portions, zircon sand 28 ~ 33 weight portions, bentonite 1 ~ 4 weight portion, waterglass 0.5 ~ 1.5 weight portion, sodium carboxymethylcellulose 1 ~ 2.5 weight portion, n-octyl alcohol 0.2 ~ 0.5 weight portion, AEO 0.2 ~ 0.5 weight portion.
Through embodiment, technical scheme of the present invention is elaborated, but protection scope of the present invention is not limited to said embodiment below.
Embodiment 1
Prepare lost foam paint according to following steps: A. adds water 10 weight portions with bentonite 1 weight portion, stirs into bentonite slurry; B. silica flour 27 weight portions, zircon sand 33 weight portions are stirred in milling apparatus, add entry 70 weight portions then, make that powder is moistening and stir, as aggregate; C. after waterglass 1.5 weight portions, sodium carboxymethylcellulose 1 weight portion, n-octyl alcohol 0.5 weight portion and AEO 0.5 weight portion being mixed, add entry 20 weight portions, be mixed with the aqueous solution; D. the said aggregate that said bentonite slurry that steps A is made and step B make adds in the said aqueous solution that step C makes, and makes coating after fully mixing.
Wherein, adding the amount of entry in said each step can be according to producing the needs free adjustment.
Embodiment 2
Prepare lost foam paint according to following steps: A. adds water 30 weight portions with bentonite 4 weight portions, becomes bentonite slurry in 6 hours with the rotating speed high-speed stirred more than the 1000rpm; B. silica flour 22 weight portions, zircon sand 28 weight portions are stirred in milling apparatus, add entry 55 weight portions then, make that powder is moistening and stir, as aggregate; C. after waterglass 0.5 weight portion, sodium carboxymethylcellulose 2.5 weight portions, n-octyl alcohol 0.2 weight portion and AEO 0.2 weight portion being mixed, add entry 15 weight portions, be mixed with the aqueous solution; D. the said aggregate that said bentonite slurry that steps A is made and step B make adds in the said aqueous solution that step C makes, and makes coating after fully mixing.
Wherein, consider for bentonite and water are fully mixed, preferably in steps A with the rotating speed high-speed stirred more than the 1000rpm 6 hours.
Embodiment 3
Prepare lost foam paint according to following steps: A. adds water 30 weight portions with bentonite 3 weight portions, stirs into bentonite slurry; B. silica flour 24 weight portions, zircon sand 30 weight portions are stirred in milling apparatus, add entry 70 weight portions then, make that powder is moistening and stir, as aggregate; C. after waterglass 1.3 weight portions, sodium carboxymethylcellulose 2 weight portions, n-octyl alcohol 0.3 weight portion and AEO 0.4 weight portion being mixed, add entry 20 weight portions, be mixed with the aqueous solution; D. the said aggregate that said bentonite slurry that steps A is made and step B make adds in the said aqueous solution that step C makes; With the rotating speed high-speed stirred more than the 1000rpm after 1 hour; Keep the following rotating speed stirring at low speed of 600rpm 10 hours, and made coating after fully mixing.
Wherein, For each composition of coating is mixed; And fully discharge the gas that is involved in the coating; The hybrid mode of step D is preferably: after 1 hour, stirring at low speed is discharged and is involved in the gas in the coating again with the rotating speed high-speed stirred more than the 1000rpm in elder generation, keeps the following rotating speed stirring at low speed of 600rpm 10 hours.
Embodiment 4
Prepare lost foam paint according to following steps: A. adds water 20 weight portions with bentonite 2 weight portions, becomes bentonite slurry in 6 hours with the rotating speed high-speed stirred more than the 1000rpm; B. silica flour 25 weight portions, zircon sand 30 weight portions are stirred in milling apparatus, add entry 60 weight portions then, make that powder is moistening and stir, as aggregate; C. after waterglass 1 weight portion, sodium carboxymethylcellulose 1.5 weight portions, n-octyl alcohol 0.3 weight portion and AEO 0.3 parts by weight being mixed, add entry 20 weight portions, be mixed with the aqueous solution; D. the said aggregate that said bentonite slurry that steps A is made and step B make adds in the said aqueous solution that step C makes; With the rotating speed high-speed stirred more than the 1000rpm after 1 hour; Keep the following rotating speed stirring at low speed of 600rpm 10 hours, and made coating after fully mixing.
Comparative example
Lost foam paint of the foregoing description 1 ~ 4 and common on the market lost foam paint are carried out following contrast experiment:
Disappearance mould apperance at first immerses coating, takes out the back dried.Can hang according to the foundry goods situation and to be coated with the repetition said process 2-5 time. the gas forming amount when reducing cast; Guarantee casting quality, must dry after foam plastics mould is coated with and coats, guarantee to make enough drying times coating oven dry, baking to pass through; Temperature is controlled at the 40-60 degree; Time 2-8 hour, use microwave drying dry in case of necessity, can accomplish dry run in the short time.
Casting: then model is placed to fill out in the sandbox and do sand, shake consolidation, and covered with plastic film is to vacuumizing in the sandbox on sandbox, after the casting, the disappearance mould gasifies, and molten metal is filled into, after cooling, takes out foundry goods.
Experimental result proves, uses the coating of the embodiment of the invention 1 ~ 4, and after the foundry goods cooling, most of smear is peeled off from cast(ing) surface automatically, peels off remarkably productive.Even the coating that few part is not peeled off, subsequent treatment is also greatly simplified, and has saved a large amount of manual works.And use common on the market lost foam paint to be difficult to from cast(ing) surface peel off, increased considerably follow-up polishing cost.
Analyze through the coating relic, behind the coating of the use embodiment of the invention 1 ~ 4, coating is invaded by molten steel, and the glassy phase that is melted between the refractory aggregate particle of coating internal layer is filled, and has stoped the invasion of molten steel.Casting quality is apparently higher than the foundry goods that uses common on the market lost foam paint.
Through test, each performance indications of the lost foam paint that method for preparing obtains are as shown in table 1.
Table 1
In sum, adopt lost foam paint provided by the invention, have splendidly when peeling off effect, permeability is excellent.That is, can prevent pore, slag inclusion phenomenon effectively, improve the quality of foundry goods.The coating of coating is easy to peel off from cast(ing) surface, and subsequent treatment is simple, saves a large amount of manual works.The performance indications of coating each side are excellent.
Invention discloses as above with preferred embodiment; Right its is not that any person of ordinary skill in the field is in spirit that does not break away from the present invention and scope in order to qualification the present invention; When can doing a little change and improvement, so the present invention's protection domain is as the criterion when looking the claim person of defining.
Claims (8)
1. lost foam paint; It is characterized in that; Comprise following component: silica flour 22 ~ 27 weight portions, zircon sand 28 ~ 33 weight portions, bentonite 1 ~ 4 weight portion, waterglass 0.5 ~ 1.5 weight portion, sodium carboxymethylcellulose 1 ~ 2.5 weight portion, n-octyl alcohol 0.2 ~ 0.5 weight portion, AEO 0.2 ~ 0.5 weight portion.
2. lost foam paint according to claim 1; It is characterized in that; The proportioning of said each component is following: silica flour 27 weight portions, zircon sand 33 weight portions, bentonite 1 weight portion, waterglass 1.5 weight portions, sodium carboxymethylcellulose 1 weight portion, n-octyl alcohol 0.5 weight portion, AEO 0.5 weight portion.
3. lost foam paint according to claim 1; It is characterized in that; The proportioning of said each component is following: silica flour 22 weight portions, zircon sand 28 weight portions, bentonite 4 weight portions, waterglass 0.5 weight portion, sodium carboxymethylcellulose 2.5 weight portions, n-octyl alcohol 0.2 weight portion, AEO 0.2 weight portion.
4. lost foam paint according to claim 1; It is characterized in that; The proportioning of said each component is following: silica flour 24 weight portions, zircon sand 30 weight portions, bentonite 3 weight portions, waterglass 1.3 weight portions, sodium carboxymethylcellulose 2 weight portions, n-octyl alcohol 0.3 weight portion, AEO 0.4 weight portion.
5. lost foam paint according to claim 1; It is characterized in that; The proportioning of said each component is following: silica flour 25 weight portions, zircon sand 30 weight portions, bentonite 2 weight portions, waterglass 1 weight portion, sodium carboxymethylcellulose 1.5 weight portions, n-octyl alcohol 0.3 weight portion, AEO 0.3 weight portion.
6. the preparation method of the described lost foam paint of claim 1 is characterized in that, comprises following steps:
A. bentonite is added water, stir into bentonite slurry;
B. silica flour, zircon sand are stirred in milling apparatus, add entry then, make that powder is moistening and stir, as aggregate;
C. after waterglass, sodium carboxymethylcellulose, n-octyl alcohol and AEO being mixed, add entry, be mixed with the aqueous solution;
D. the said aggregate that said bentonite slurry that steps A is made and step B make adds in the said aqueous solution that step C makes, and fully mixes.
7. the preparation method of lost foam paint according to claim 6 is characterized in that, the alr mode of said steps A is specially: with the rotating speed high-speed stirred more than the 1000rpm 6 hours.
8. according to the preparation method of claim 6 or 7 described lost foam paints, it is characterized in that the hybrid mode of said step D is specially: after 1 hour, kept the following rotating speed stirring at low speed of 600rpm 10 hours with the rotating speed high-speed stirred more than the 1000rpm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012103204317A CN102836957A (en) | 2012-08-31 | 2012-08-31 | Lost foam coating and preparation method thereof |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012103204317A CN102836957A (en) | 2012-08-31 | 2012-08-31 | Lost foam coating and preparation method thereof |
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| CN102836957A true CN102836957A (en) | 2012-12-26 |
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| CN2012103204317A Pending CN102836957A (en) | 2012-08-31 | 2012-08-31 | Lost foam coating and preparation method thereof |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103357813A (en) * | 2013-07-24 | 2013-10-23 | 翼城县福旺铸造实业有限公司 | Lost foam steel-casting paint formula and technology method thereof |
| CN103658510A (en) * | 2013-12-25 | 2014-03-26 | 芜湖瑞鹄铸造有限公司 | Water-based paint for cavityless casting |
| CN104226907A (en) * | 2014-09-30 | 2014-12-24 | 无锡康柏斯机械科技有限公司 | Lost foam casting process capable of compacting sand further |
| CN105884266A (en) * | 2016-04-06 | 2016-08-24 | 郑州远东耐火材料有限公司 | Large electrically-fused brick sand mold coating |
| CN108746481A (en) * | 2018-05-25 | 2018-11-06 | 西峡县西保冶金材料有限公司 | A kind of mould coating material and preparation method thereof |
| CN110156461A (en) * | 2019-04-29 | 2019-08-23 | 曹博海 | A kind of disappearance alloy for die casting steel coating and preparation method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103357813A (en) * | 2013-07-24 | 2013-10-23 | 翼城县福旺铸造实业有限公司 | Lost foam steel-casting paint formula and technology method thereof |
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| CN104226907A (en) * | 2014-09-30 | 2014-12-24 | 无锡康柏斯机械科技有限公司 | Lost foam casting process capable of compacting sand further |
| CN105884266A (en) * | 2016-04-06 | 2016-08-24 | 郑州远东耐火材料有限公司 | Large electrically-fused brick sand mold coating |
| CN105884266B (en) * | 2016-04-06 | 2018-06-26 | 郑州远东耐火材料有限公司 | A kind of large size fused cast refractories mo(u)ld blacking |
| CN108746481A (en) * | 2018-05-25 | 2018-11-06 | 西峡县西保冶金材料有限公司 | A kind of mould coating material and preparation method thereof |
| CN110156461A (en) * | 2019-04-29 | 2019-08-23 | 曹博海 | A kind of disappearance alloy for die casting steel coating and preparation method thereof |
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Application publication date: 20121226 |