CN108608687B - Foamed aluminum acoustic board capable of effectively reducing urban traffic noise and preparation method thereof - Google Patents

Foamed aluminum acoustic board capable of effectively reducing urban traffic noise and preparation method thereof Download PDF

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Publication number
CN108608687B
CN108608687B CN201810397673.3A CN201810397673A CN108608687B CN 108608687 B CN108608687 B CN 108608687B CN 201810397673 A CN201810397673 A CN 201810397673A CN 108608687 B CN108608687 B CN 108608687B
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parts
aluminum
foamed aluminum
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foamed
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CN108608687A (en
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段国凡
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Changzhou Chiyi plastic products Co.,Ltd.
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Changzhou Chiyi Plastic Products Co ltd
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/10—Sintering only
    • B22F3/11—Making porous workpieces or articles
    • B22F3/1121—Making porous workpieces or articles by using decomposable, meltable or sublimatable fillers
    • B22F3/1137—Making porous workpieces or articles by using decomposable, meltable or sublimatable fillers by coating porous removable preforms
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/10—Metallic powder containing lubricating or binding agents; Metallic powder containing organic material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/10—Metallic powder containing lubricating or binding agents; Metallic powder containing organic material
    • B22F1/103—Metallic powder containing lubricating or binding agents; Metallic powder containing organic material containing an organic binding agent comprising a mixture of, or obtained by reaction of, two or more components other than a solvent or a lubricating agent
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/10—Sintering only
    • B22F3/11—Making porous workpieces or articles
    • B22F3/1121—Making porous workpieces or articles by using decomposable, meltable or sublimatable fillers
    • B22F3/1125—Making porous workpieces or articles by using decomposable, meltable or sublimatable fillers involving a foaming process
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B15/00—Layered products comprising a layer of metal
    • B32B15/04—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material
    • B32B15/046—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material of foam
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B15/00—Layered products comprising a layer of metal
    • B32B15/20—Layered products comprising a layer of metal comprising aluminium or copper
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
    • B32B5/18—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by features of a layer of foamed material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2266/00—Composition of foam
    • B32B2266/04—Inorganic
    • B32B2266/045—Metal
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2307/00—Properties of the layers or laminate
    • B32B2307/10—Properties of the layers or laminate having particular acoustical properties
    • B32B2307/102—Insulating

Abstract

The invention discloses a foamed aluminum acoustic board for effectively reducing urban traffic noise, which comprises an aluminum plate body, wherein foamed aluminum materials are adhered to the surfaces of two sides of the aluminum plate body, and the foamed aluminum materials comprise the following raw materials: aluminum scraps, deionized water, ultrapure water, absolute ethyl alcohol, a dispersing agent, a plasticizer, an adhesive and a foaming agent; the adhesive consists of the following raw materials: starch, polyvinyl alcohol, polyurethane, butyl rubber, vinyl acetate resin and water-based organic silicon epoxy resin; the foaming agent consists of the following raw materials: azodicarbonamide, sodium bicarbonate, carbon black, n-hexane, trichlorofluoromethane, sodium dodecyl sulfate; the foamed aluminum material has a through hole porosity of 98.5-99.8% and an average through hole diameter of 0.75-0.85 mm; the thickness of the foamed aluminum material stuck on the two side surfaces of the aluminum plate body is 20-25 mm; the sound absorption coefficient of the foamed aluminum sound absorption plate is 0.88-0.92. The invention solves the technical problems of uneven pore diameter of the through hole, larger pore diameter of the through hole and lower porosity of the through hole in the existing foamed aluminum material.

Description

Foamed aluminum acoustic board capable of effectively reducing urban traffic noise and preparation method thereof
Technical Field
The invention relates to the technical field of new materials, in particular to a foamed aluminum acoustic board capable of effectively reducing urban traffic noise and a preparation method thereof.
Background
With the development of economy, the urbanization scale is enlarged, the traffic trunk line is rapidly developed, the number of motor vehicles in cities is rapidly increased, and traffic noise increasingly becomes the main noise of the cities.
The porous metal is composed of a metal skeleton and pores, and has basic metal properties such as weldability of a metal material. A notable feature of porous metals, relative to dense metal materials, is that they have a large number of pores within them. The large amount of internal pores in turn allows the porous metal material to have excellent properties. The porous organic polymer material has low strength and is not high temperature resistant, and the porous ceramic material is brittle and is not thermal shock resistant, so the porous metal material is applied to the silencing process to manufacture the silencer.
Foamed aluminum is a porous metal material, and has excellent physical, chemical and mechanical properties and recyclability. The excellent properties of the foamed aluminum enable the foamed aluminum to have wide application prospects in the field of current materials, and the foamed aluminum is a novel engineering material with development prospects. The foamed aluminum can be used for noise control of urban light rails, elevated highways, underground tunnels and mechanical equipment and improvement of sound effects in acoustic rooms, multi-functional halls and other rooms. The sound-absorbing foamed aluminum is pasted on concrete or a steel structure and erected on two sides of the viaduct and the light rail to serve as a large sound-absorbing wall, so that urban traffic noise can be reduced.
However, the conventional foamed aluminum material has the problems of non-uniform pore size, large pore size and low porosity of the through holes, and the problems seriously affect the sound absorption effect of the foamed aluminum material.
Disclosure of Invention
Technical problem to be solved
Aiming at the defects of the prior art, the invention provides the foamed aluminum acoustic board for effectively reducing urban traffic noise and the preparation method thereof, which have the advantages of improving the porosity of through holes, reducing the aperture of the through holes, obviously improving the sound absorption coefficient and the like, and solve the technical problems of uneven aperture size of the through holes, larger aperture of the through holes and lower porosity of the through holes of the existing foamed aluminum material.
(II) technical scheme
In order to achieve the purposes of improving the porosity of the through hole, reducing the aperture of the through hole and obviously improving the sound absorption coefficient, the invention provides the following technical scheme:
the utility model provides an effectively alleviate city traffic noise's foamed aluminum abatvoix, includes the aluminum plate body, all paste foamed aluminum material on the both sides surface of aluminum plate body, this foamed aluminum material includes the raw materials of following parts by weight ratio: 35-50 parts of aluminum scraps, 60-70 parts of deionized water, 150 parts of 100-one ultrapure water, 70-100 parts of absolute ethyl alcohol, 12-22 parts of dispersing agent, 5-12 parts of plasticizer, 20-32 parts of adhesive and 23-33 parts of foaming agent;
the dispersing agent is prepared from the following raw materials in parts by weight: 1-3 parts of sodium pyrophosphate, 1-3 parts of sodium metasilicate, 3-5 parts of polyethylene glycol alkyl aryl ether sodium sulfonate, 2-5 parts of polyethylene pyrrolidone and 5-6 parts of polyethylene glycol;
the plasticizer is composed of the following raw materials in parts by weight: 2-4 parts of dibutyl phthalate, 1-5 parts of dimethyl phthalate and 2-3 parts of diethyl phthalate;
the adhesive is prepared from the following raw materials in parts by weight: 5-7 parts of starch, 5-8 parts of polyvinyl alcohol, 5-6 parts of polyurethane, 1-3 parts of butyl rubber, 2-3 parts of vinyl acetate resin and 2-5 parts of water-based organic silicon epoxy resin;
the foaming agent is composed of the following raw materials in parts by weight: 2-5 parts of azodicarbonamide, 1-2 parts of sodium bicarbonate, 12-15 parts of carbon black, 1-2 parts of n-hexane, 2-3 parts of trichlorofluoromethane and 5-6 parts of sodium dodecyl sulfate;
the porosity of the through holes of the foamed aluminum material is 98.5-99.8%, and the average pore diameter of the through holes is 0.75-0.85 mm;
the thickness of the aluminum plate body is 20-30mm, and the thickness of the foamed aluminum material adhered to the two side surfaces of the aluminum plate body is 20-25 mm;
the sound absorption coefficient of the foamed aluminum sound absorption plate is 0.88-0.92.
Preferably, the foamed aluminum material comprises the following raw materials in parts by weight: 40 parts of aluminum scraps, 70 parts of deionized water, 150 parts of ultrapure water, 100 parts of absolute ethyl alcohol, 17 parts of a dispersing agent, 10 parts of a plasticizer, 26 parts of an adhesive and 27 parts of a foaming agent.
Preferably, the dispersing agent is composed of the following raw materials in parts by weight: 2 parts of sodium pyrophosphate, 2 parts of sodium metasilicate, 4 parts of polyethylene glycol alkyl aryl ether sodium sulfonate, 4 parts of polyethylene pyrrolidone and 5 parts of polyethylene glycol.
Preferably, the plasticizer is prepared from the following raw materials in parts by weight: 3 parts of dibutyl phthalate, 4 parts of dimethyl phthalate and 3 parts of diethyl phthalate.
Preferably, the adhesive is prepared from the following raw materials in parts by weight: 6 parts of starch, 6 parts of polyvinyl alcohol, 5 parts of polyurethane, 2 parts of butyl rubber, 3 parts of vinyl acetate resin and 4 parts of water-based organic silicon epoxy resin.
Preferably, the foaming agent is prepared from the following raw materials in parts by weight: 3 parts of azodicarbonamide, 1 part of sodium bicarbonate, 14 parts of carbon black, 1 part of n-hexane, 2 parts of trichlorofluoromethane and 6 parts of sodium dodecyl sulfate.
Preferably, the thickness of the aluminum plate body is 25mm, and the thickness of the foamed aluminum material adhered to the two side surfaces of the aluminum plate body is 25 mm.
The invention aims to solve another technical problem of providing a preparation method of a foamed aluminum acoustic board for effectively reducing urban traffic noise, which comprises the following steps:
(1) adding 35-50 parts by mass of aluminum scraps into 35-50 parts by mass of absolute ethyl alcohol, mixing and stirring uniformly, soaking for 20-30min, washing the filtered aluminum scraps with 50-75 parts by mass of ultrapure water, placing in a vacuum drying oven, drying at the temperature of 100-50 ℃ for 60-80min, taking out, adding the aluminum scraps into 35-50 parts by mass of absolute ethyl alcohol, and soaking for 40-60min to obtain an aluminum scrap alcohol solution;
(2) adding the aluminum scrap alcohol solution prepared in the step (1) into 60-70 parts by mass of deionized water, stirring at the speed of 300-350r/min for 10min at room temperature, then adding 12-22 parts by mass of dispersing agents, namely 1-3 parts of sodium pyrophosphate, 1-3 parts of sodium metasilicate, 3-5 parts of polyethylene glycol alkyl aryl ether sodium sulfonate, 2-5 parts of polyethylene phthalimide and 5-6 parts of polyethylene glycol, fully stirring and mixing at room temperature, and uniformly dispersing the aluminum scrap into the dispersing liquid by adopting a mode of ultrasonic frequency of 20-25kHz and ultrasonic time of 30-60min to prepare the dispersing liquid;
(3) adding 5-12 parts by mass of plasticizer, namely 2-4 parts of dibutyl phthalate, 1-5 parts of dimethyl phthalate and 2-3 parts of diethyl phthalate into the dispersion prepared in the step (2), stirring at the temperature of 30-40 ℃ for 500r/min at the stirring speed of 400-, 5-8 parts of polyvinyl alcohol, 5-6 parts of polyurethane, 1-3 parts of butyl rubber, 2-3 parts of vinyl acetate resin and 2-5 parts of water-based organic silicon epoxy resin, and stirring at the temperature of 40-50 ℃ and the stirring speed of 800-850r/min for 60-90min to obtain viscous dispersion liquid;
(4) soaking foam cotton into the viscous dispersion liquid obtained in the step (3), placing the foam cotton into a mold after adsorption saturation, and cooling and curing at the curing temperature of 3-5 ℃;
(5) sintering the foamed aluminum cotton in the mold at the temperature of 100-150 ℃ for 1-2h, at the temperature of 150-200 ℃ for 2-3h, at the temperature of 200-300 ℃ for 2-3h, at the temperature of 300-400 ℃ for 2-3h, at the temperature of 400-500 ℃ for 1-2h, at the temperature of 500-600 ℃ for 1-2h, at the temperature of 600-800 ℃ for 3-4h, after sintering at the temperature of 800-850 ℃ for 1-2h, naturally cooling to room temperature, washing with 40-50 parts by mass of anhydrous ethanol, then washing with 50-75 parts by mass of ultrapure water, and obtaining the foamed aluminum material after washing;
(6) and (3) respectively bonding the foamed aluminum material prepared in the step (5) on the two side surfaces of the aluminum plate body with the thickness of 20-30mm, wherein the foamed aluminum material bonded on the two side surfaces of the aluminum plate body has the thickness of 20-25 mm.
(III) advantageous effects
Compared with the prior art, the invention provides an effective method, which has the following beneficial effects:
1. the foamed aluminum sound-absorbing board is prepared by preparing a foamed aluminum material with the through hole porosity of 98.5-99.8% and the average through hole diameter of 0.75-0.85mm, and the foamed aluminum material has the through hole porosity of 98.5-99.8% and the through hole diameter of 0.75-0.85mm, so that the through hole porosity of the foamed aluminum material is obviously improved, the through hole diameter of the foamed aluminum material is more uniform while the through hole diameter of the foamed aluminum material is obviously reduced, the technical problems of uneven through hole diameter, larger through hole diameter and lower through hole porosity of the conventional foamed aluminum material are solved, the sound-absorbing capacity of the foamed aluminum material can be obviously improved due to higher through hole porosity and smaller through hole diameter, and the technical effect of reducing urban traffic noise can be effectively realized.
2. According to the foamed aluminum acoustic board, the foamed aluminum materials are adhered to the surfaces of the two sides of the aluminum plate body to form the foamed aluminum acoustic board, the foamed aluminum acoustic board is erected on two sides of the viaduct and the light rail, and the sound absorption coefficient of the foamed aluminum acoustic board is 0.88-0.92 through testing, so that the foamed aluminum acoustic board achieves the technical effect of remarkable sound absorption.
3. According to the foamed aluminum acoustic board, the foaming agent is prepared from azodicarbonamide, sodium bicarbonate, carbon black, normal hexane, trichlorofluoromethane and lauryl sodium sulfate in parts by weight, and the foaming agent contains three chemical foaming agents, namely azodicarbonamide, sodium bicarbonate, carbon black and the like, and the chemical foaming agent can release gases such as carbon dioxide, nitrogen and the like after being heated and decomposed, so that aluminum can effectively form uniform pores in the polymerization process, and the pore size of the foamed aluminum material is reduced; in addition, the foaming agent contains sodium dodecyl sulfate which is used as a surfactant foaming agent, has high surface activity, can effectively reduce the surface tension of liquid, is arranged on the surface of a liquid film in a double-electron layer manner to surround air, forms more bubbles, and accordingly improves the porosity of the foamed aluminum material.
4. According to the preparation method of the foamed aluminum sound-absorbing board, the foamed aluminum material is prepared firstly, a gradient temperature rise sintering mode is adopted when the foamed aluminum material is prepared, and then the foamed aluminum material is pasted on the surfaces of the two sides of the aluminum plate body, so that the foamed aluminum sound-absorbing board is prepared.
5. According to the preparation method of the foamed aluminum sound-absorbing board, the foamed cotton is adopted as the absorbent in the process of preparing the foamed aluminum material, and the foamed cotton has higher porosity and smaller and uniform pore size, so that the prepared foamed aluminum material also has higher porosity and smaller and uniform pore size, and the technical problems of uneven pore size, larger pore size and lower porosity of through holes of the existing foamed aluminum material are solved.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The first embodiment is as follows:
(1) adding 35 parts by mass of aluminum scraps into 35 parts by mass of absolute ethyl alcohol, mixing and stirring uniformly, soaking for 20min, washing the filtered aluminum scraps with 50 parts by mass of ultrapure water, placing in a vacuum drying oven, drying at 100 ℃ for 60min, taking out, adding the aluminum scraps into 35 parts by mass of absolute ethyl alcohol, and soaking for 40min to obtain an aluminum scrap alcohol solution;
(2) adding the aluminum skimming alcohol solution prepared in the step (1) into 60 parts by mass of deionized water, stirring at the stirring speed of 300r/min for 10min at room temperature, then adding 12 parts by mass of dispersing agents, namely 1 part of sodium pyrophosphate, 1 part of sodium metasilicate, 3 parts of polyethylene glycol alkyl aryl ether sodium sulfonate, 2 parts of polyethylene pyrrolidone and 5 parts of polyethylene glycol, fully stirring and mixing at room temperature, and uniformly dispersing aluminum skimming into a dispersion liquid in a mode that the ultrasonic frequency is 20kHz and the ultrasonic time is 30min to prepare the dispersion liquid;
(3) adding 5 parts by mass of a plasticizer to the dispersion liquid prepared in the step (2), namely 2 parts of dibutyl phthalate, 1 part of dimethyl phthalate and 2 parts of diethyl phthalate, stirring at 30 ℃ and a stirring speed of 400r/min for 20min, then adding 23 parts by mass of foaming agent, namely 2 parts of azodicarbonamide, 1 part of sodium bicarbonate, 12 parts of carbon black, 1 part of normal hexane, 2 parts of trichlorofluoromethane and 5 parts of lauryl sodium sulfate, stirring at 35 deg.C and 500r/min for 40min, adding 20 parts by weight of binder, namely 5 parts of starch, 5 parts of polyvinyl alcohol, 5 parts of polyurethane, 1 part of butyl rubber, 2 parts of vinyl acetate resin and 2 parts of water-based organic silicon epoxy resin, stirring at 40 deg.C and stirring speed of 800r/min for 60min to obtain viscous dispersion;
(4) soaking foam cotton into the viscous dispersion liquid obtained in the step (3), placing the foam cotton into a mold after adsorption saturation, and cooling and curing at the curing temperature of 3 ℃;
(5) sintering the foamed aluminum cotton in the mold at 100 ℃ for 1h, at 150 ℃ for 2h, at 200 ℃ for 2h, at 300 ℃ for 2h, at 400 ℃ for 1h, at 500 ℃ for 1h, at 600 ℃ for 3h, at 800 ℃ for 1h, naturally cooling, cooling to room temperature, washing with 40 parts by mass of absolute ethyl alcohol, then washing with 50 parts by mass of ultrapure water, and obtaining the foamed aluminum material after washing;
(6) and (3) respectively bonding the foamed aluminum material prepared in the step (5) on the two side surfaces of the aluminum plate body with the thickness of 20mm, wherein the foamed aluminum material bonded on the two side surfaces of the aluminum plate body has the thickness of 20 mm.
Example two:
(1) adding 40 parts by mass of aluminum scraps into 50 parts by mass of absolute ethyl alcohol, mixing and stirring uniformly, soaking for 25min, washing the filtered aluminum scraps with 75 parts by mass of ultrapure water, placing in a vacuum drying oven, drying at 105 ℃ for 70min, taking out, adding the aluminum scraps into 50 parts by mass of absolute ethyl alcohol, and soaking for 50min to obtain an aluminum scrap alcohol solution;
(2) adding the aluminum skimming alcohol solution prepared in the step (1) into 70 parts by mass of deionized water, stirring at the stirring speed of 320r/min for 10min at room temperature, then adding 17 parts by mass of dispersing agents, namely 2 parts of sodium pyrophosphate, 2 parts of sodium metasilicate, 4 parts of polyethylene glycol alkyl aryl ether sodium sulfonate, 4 parts of polyethylene pyrrolidone and 5 parts of polyethylene glycol, fully stirring and mixing at room temperature, and uniformly dispersing aluminum skimming into a dispersion liquid in a mode that the ultrasonic frequency is 24kHz and the ultrasonic time is 40min to prepare the dispersion liquid;
(3) adding 10 parts by mass of a plasticizer to the dispersion liquid prepared in the step (2), namely 3 parts of dibutyl phthalate, 4 parts of dimethyl phthalate and 3 parts of diethyl phthalate, stirring at the temperature of 35 ℃ and the stirring speed of 450r/min for 25min, then adding 27 parts by mass of foaming agent, namely 3 parts of azodicarbonamide, 1 part of sodium bicarbonate, 14 parts of carbon black, 1 part of normal hexane, 2 parts of trichlorofluoromethane and 6 parts of lauryl sodium sulfate, stirring at the temperature of 38 ℃ and the stirring speed of 530r/min for 50min, then adding 26 parts by mass of adhesive, namely 6 parts of starch, 6 parts of polyvinyl alcohol, 5 parts of polyurethane, 2 parts of butyl rubber, 3 parts of vinyl acetate resin and 4 parts of water-based organic silicon epoxy resin, stirring at 45 deg.C and 830r/min for 80min to obtain viscous dispersion;
(4) soaking foam cotton into the viscous dispersion liquid obtained in the step (3), placing the foam cotton into a mold after adsorption saturation, and cooling and curing at the curing temperature of 4 ℃;
(5) sintering the foamed aluminum cotton in the mold at 120 ℃ for 1.5h, at 160 ℃ for 2.5h, at 250 ℃ for 2.5h, at 350 ℃ for 2.5h, at 450 ℃ for 1.5h, at 550 ℃ for 1.5h, at 700 ℃ for 3.5h, at 850 ℃ for 1.5h, naturally cooling, cooling to room temperature, washing with 45 parts by mass of absolute ethyl alcohol, washing with 75 parts by mass of ultrapure water, and obtaining the foamed aluminum material after washing;
(6) and (3) respectively bonding the foamed aluminum material prepared in the step (5) on the two side surfaces of the aluminum plate body with the thickness of 25mm, wherein the foamed aluminum material adhered on the two side surfaces of the aluminum plate body has the thickness of 25 mm.
Example three:
(1) adding 50 parts by mass of aluminum scraps into 50 parts by mass of absolute ethyl alcohol, mixing and stirring uniformly, soaking for 30min, washing the filtered aluminum scraps with 75 parts by mass of ultrapure water, placing in a vacuum drying oven, drying at the temperature of 110 ℃ for 80min, taking out, adding the aluminum scraps into 50 parts by mass of absolute ethyl alcohol, and soaking for 60min to obtain an aluminum scrap alcohol solution;
(2) adding the aluminum skimming alcohol solution prepared in the step (1) into 70 parts by mass of deionized water, stirring at the stirring speed of 350r/min for 10min at room temperature, then adding 22 parts by mass of dispersing agents, namely 3 parts of sodium pyrophosphate, 3 parts of sodium metasilicate, 5 parts of polyethylene glycol alkyl aryl ether sodium sulfonate, 5 parts of polyethylene pyrrolidone and 6 parts of polyethylene glycol, fully stirring and mixing at room temperature, and uniformly dispersing aluminum skimming into a dispersion liquid by adopting a mode that the ultrasonic frequency is 25kHz and the ultrasonic time is 60min to prepare the dispersion liquid;
(3) adding 12 parts by mass of a plasticizer to the dispersion liquid prepared in the step (2), namely 4 parts of dibutyl phthalate, 5 parts of dimethyl phthalate and 3 parts of diethyl phthalate, stirring at 40 deg.C and stirring speed of 500r/min for 30min, adding 33 parts by mass of foaming agent, namely 5 parts of azodicarbonamide, 2 parts of sodium bicarbonate, 15 parts of carbon black, 2 parts of normal hexane, 3 parts of trichlorofluoromethane and 6 parts of lauryl sodium sulfate, stirring at the temperature of 40 ℃ and the stirring speed of 550r/min for 60min, then adding 20-32 parts by mass of adhesive, namely 7 parts of starch, 8 parts of polyvinyl alcohol, 6 parts of polyurethane, 3 parts of butyl rubber, 3 parts of vinyl acetate resin and 5 parts of water-based organic silicon epoxy resin, stirring at 50 deg.C and stirring speed of 850r/min for 90min to obtain viscous dispersion;
(4) soaking foam cotton into the viscous dispersion liquid obtained in the step (3), placing the foam cotton into a mold after adsorption saturation, and cooling and curing at the curing temperature of 5 ℃;
(5) sintering the foamed aluminum cotton in the mold at 150 ℃ for 2h, at 200 ℃ for 3h, at 300 ℃ for 3h, at 400 ℃ for 3h, at 500 ℃ for 2h, at 600 ℃ for 2h, at 800 ℃ for 4h, at 850 ℃ for 2h, naturally cooling, cooling to room temperature, washing with 50 parts by mass of absolute ethyl alcohol, then washing with 75 parts by mass of ultrapure water, and obtaining the foamed aluminum material after washing;
(6) and (3) respectively bonding the foamed aluminum material prepared in the step (5) on the two side surfaces of the aluminum plate body with the thickness of 30mm, wherein the foamed aluminum material adhered on the two side surfaces of the aluminum plate body has the thickness of 25 mm.
Experimental example: the foamed aluminum acoustic panels prepared in example 1, example 2 and example 3 were measured for their random incidence sound absorption coefficient by standing wave tube method, and the test results are shown in table 1, and the through-hole porosity and through-hole pore diameter by scanning electron microscope are shown in table 2.
And (4) judging the standard: the sound absorption capacity of a certain material or structure is expressed by a sound absorption coefficient alpha. The sound absorption coefficient alpha is equal to the ratio of the sound energy absorbed by the material (including transmitted sound energy) to the total sound energy incident on the material, i.e. the sound absorption coefficient alpha is equal to the ratio of the sound energy absorbed by the material (including transmitted sound energy) to the total sound energy incident on the material
α＝(Ea+Et)/E＝(E-Er)/E＝1-γ
In the formula: e-total acoustic energy (J), E) incident to the materialaAcoustic energy (J), E) absorbed by the materialtAcoustic energy (J), E) transmitted through the materialr-acoustic energy (J), gamma-reflection coefficient, reflected by the material;
when alpha is 0, the acoustic energy is totally reflected, and the material does not absorb sound; when α is 1, it means that the material absorbs all the sound energy and does not reflect. The sound absorption coefficient of the general material is between 0 and 1, and the larger the sound absorption coefficient alpha is, the better the sound absorption performance of the material is.
The average sound absorption coefficient of a certain material is generally represented by the arithmetic mean value of sound absorption coefficients of six frequencies of 125Hz, 250Hz, 500Hz, 1000Hz, 2000Hz and 4000Hz in engineering. Generally, materials with an average sound absorption coefficient >0.2 are referred to as sound absorbers, and materials with an average sound absorption coefficient >0.5 are ideal sound absorbers.
TABLE 1
TABLE 2
Examples Porosity of through hole (%) Aperture of through hole (mm)
Example 1 98.5 0.81
Example 2 99.8 0.75
Example 3 99.1 0.85
The invention has the beneficial effects that: as can be seen from table 1, the average sound absorption coefficients of examples 1, 2 and 3 were 0.90, 0.92 and 0.88, respectively, and were all greater than 0.5, and therefore the foamed aluminum sound-absorbing sheet was a desirable sound-absorbing material.
Typical cases are as follows: (1) adding 40 parts by mass of aluminum scraps into 50 parts by mass of absolute ethyl alcohol, mixing and stirring uniformly, soaking for 25min, washing the filtered aluminum scraps with 75 parts by mass of ultrapure water, placing in a vacuum drying oven, drying at 105 ℃ for 70min, taking out, adding the aluminum scraps into 50 parts by mass of absolute ethyl alcohol, and soaking for 50min to obtain an aluminum scrap alcohol solution;
(2) adding the aluminum skimming alcohol solution prepared in the step (1) into 70 parts by mass of deionized water, stirring at the stirring speed of 320r/min for 10min at room temperature, then adding 17 parts by mass of dispersing agents, namely 2 parts of sodium pyrophosphate, 2 parts of sodium metasilicate, 4 parts of polyethylene glycol alkyl aryl ether sodium sulfonate, 4 parts of polyethylene pyrrolidone and 5 parts of polyethylene glycol, fully stirring and mixing at room temperature, and uniformly dispersing aluminum skimming into a dispersion liquid in a mode that the ultrasonic frequency is 24kHz and the ultrasonic time is 40min to prepare the dispersion liquid;
(3) adding 10 parts by mass of a plasticizer to the dispersion liquid prepared in the step (2), namely 3 parts of dibutyl phthalate, 4 parts of dimethyl phthalate and 3 parts of diethyl phthalate, stirring at the temperature of 35 ℃ and the stirring speed of 450r/min for 25min, then adding 27 parts by mass of foaming agent, namely 3 parts of azodicarbonamide, 1 part of sodium bicarbonate, 14 parts of carbon black, 1 part of normal hexane, 2 parts of trichlorofluoromethane and 6 parts of lauryl sodium sulfate, stirring at the temperature of 38 ℃ and the stirring speed of 530r/min for 50min, then adding 26 parts by mass of adhesive, namely 6 parts of starch, 6 parts of polyvinyl alcohol, 5 parts of polyurethane, 2 parts of butyl rubber, 3 parts of vinyl acetate resin and 4 parts of water-based organic silicon epoxy resin, stirring at 45 deg.C and 830r/min for 80min to obtain viscous dispersion;
(4) soaking foam cotton into the viscous dispersion liquid obtained in the step (3), placing the foam cotton into a mold after adsorption saturation, and cooling and curing at the curing temperature of 4 ℃;
(5) sintering the foamed aluminum cotton in the mold at 120 ℃ for 1.5h, at 160 ℃ for 2.5h, at 250 ℃ for 2.5h, at 350 ℃ for 2.5h, at 450 ℃ for 1.5h, at 550 ℃ for 1.5h, at 700 ℃ for 3.5h, at 850 ℃ for 1.5h, naturally cooling, cooling to room temperature, washing with 45 parts by mass of absolute ethyl alcohol, washing with 75 parts by mass of ultrapure water, and obtaining the foamed aluminum material after washing;
(6) and (3) respectively bonding the foamed aluminum material prepared in the step (5) on the two side surfaces of an aluminum plate body with the thickness of 25mm, wherein the foamed aluminum material adhered on the two side surfaces of the aluminum plate body has the thickness of 25mm, and the absorption coefficient of the foamed aluminum sound-absorbing plate is 0.92.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims (7)

1. The foamed aluminum sound-absorbing board comprises an aluminum board body, foamed aluminum materials are pasted on the surfaces of two sides of the aluminum board body, and the foamed aluminum materials comprise the following raw materials in parts by weight: 35-50 parts of aluminum scraps, 60-70 parts of deionized water, 150 parts of 100-one ultrapure water, 70-100 parts of absolute ethyl alcohol, 12-22 parts of dispersing agent, 5-12 parts of plasticizer, 20-32 parts of adhesive and 23-33 parts of foaming agent;
the dispersing agent is prepared from the following raw materials in parts by weight: 1-3 parts of sodium pyrophosphate, 1-3 parts of sodium metasilicate, 3-5 parts of polyethylene glycol alkyl aryl ether sodium sulfonate, 2-5 parts of polyethylene pyrrolidone and 5-6 parts of polyethylene glycol;
the plasticizer is composed of the following raw materials in parts by weight: 2-4 parts of dibutyl phthalate, 1-5 parts of dimethyl phthalate and 2-3 parts of diethyl phthalate;
the adhesive is prepared from the following raw materials in parts by weight: 5-7 parts of starch, 5-8 parts of polyvinyl alcohol, 5-6 parts of polyurethane, 1-3 parts of butyl rubber, 2-3 parts of vinyl acetate resin and 2-5 parts of water-based organic silicon epoxy resin;
the foaming agent is composed of the following raw materials in parts by weight: 2-5 parts of azodicarbonamide, 1-2 parts of sodium bicarbonate, 12-15 parts of carbon black, 1-2 parts of n-hexane, 2-3 parts of trichlorofluoromethane and 5-6 parts of sodium dodecyl sulfate;
the porosity of the through holes of the foamed aluminum material is 98.5-99.8%, and the average pore diameter of the through holes is 0.75-0.85 mm;
the thickness of the aluminum plate body is 20-30mm, and the thickness of the foamed aluminum material adhered to the two side surfaces of the aluminum plate body is 20-25 mm;
the sound absorption coefficient of the foamed aluminum sound absorption plate is 0.88-0.92; the method is characterized in that: the method comprises the following steps:
(1) adding 35-50 parts by mass of aluminum scraps into 35-50 parts by mass of absolute ethyl alcohol, mixing and stirring uniformly, soaking for 20-30min, washing the filtered aluminum scraps with 50-75 parts by mass of ultrapure water, placing in a vacuum drying oven, drying at the temperature of 100-50 ℃ for 60-80min, taking out, adding the aluminum scraps into 35-50 parts by mass of absolute ethyl alcohol, and soaking for 40-60min to obtain an aluminum scrap alcohol solution;
(2) adding the aluminum scrap alcohol solution prepared in the step (1) into 60-70 parts by mass of deionized water, stirring at the speed of 300-350r/min for 10min at room temperature, then adding 12-22 parts by mass of dispersing agents, namely 1-3 parts of sodium pyrophosphate, 1-3 parts of sodium metasilicate, 3-5 parts of polyethylene glycol alkyl aryl ether sodium sulfonate, 2-5 parts of polyethylene phthalimide and 5-6 parts of polyethylene glycol, fully stirring and mixing at room temperature, and uniformly dispersing the aluminum scrap into the dispersing liquid by adopting a mode of ultrasonic frequency of 20-25kHz and ultrasonic time of 30-60min to prepare the dispersing liquid;
(3) adding 5-12 parts by mass of plasticizer, namely 2-4 parts of dibutyl phthalate, 1-5 parts of dimethyl phthalate and 2-3 parts of diethyl phthalate into the dispersion prepared in the step (2), stirring at the temperature of 30-40 ℃ for 500r/min at the stirring speed of 400-, 5-8 parts of polyvinyl alcohol, 5-6 parts of polyurethane, 1-3 parts of butyl rubber, 2-3 parts of vinyl acetate resin and 2-5 parts of water-based organic silicon epoxy resin, and stirring at the temperature of 40-50 ℃ and the stirring speed of 800-850r/min for 60-90min to obtain viscous dispersion liquid;
(4) soaking foam cotton into the viscous dispersion liquid obtained in the step (3), placing the foam cotton into a mold after adsorption saturation, and cooling and curing at the curing temperature of 3-5 ℃;
(5) sintering the foamed aluminum cotton in the mold at the temperature of 100-150 ℃ for 1-2h, at the temperature of 150-200 ℃ for 2-3h, at the temperature of 200-300 ℃ for 2-3h, at the temperature of 300-400 ℃ for 2-3h, at the temperature of 400-500 ℃ for 1-2h, at the temperature of 500-600 ℃ for 1-2h, at the temperature of 600-800 ℃ for 3-4h, after sintering at the temperature of 800-850 ℃ for 1-2h, naturally cooling to room temperature, washing with 40-50 parts by mass of anhydrous ethanol, then washing with 50-75 parts by mass of ultrapure water, and obtaining the foamed aluminum material after washing;
(6) and (3) respectively bonding the foamed aluminum material prepared in the step (5) on the two side surfaces of the aluminum plate body with the thickness of 20-30mm, wherein the foamed aluminum material bonded on the two side surfaces of the aluminum plate body has the thickness of 20-25 mm.
2. The method for preparing the foamed aluminum acoustic panel for effectively reducing the urban traffic noise according to claim 1, wherein the foamed aluminum material comprises the following raw materials in parts by weight: 40 parts of aluminum scraps, 70 parts of deionized water, 150 parts of ultrapure water, 100 parts of absolute ethyl alcohol, 17 parts of a dispersing agent, 10 parts of a plasticizer, 26 parts of an adhesive and 27 parts of a foaming agent.
3. The preparation method of the foamed aluminum acoustic panel for effectively reducing the urban traffic noise according to claim 2, wherein the dispersing agent is prepared from the following raw materials in parts by weight: 2 parts of sodium pyrophosphate, 2 parts of sodium metasilicate, 4 parts of polyethylene glycol alkyl aryl ether sodium sulfonate, 4 parts of polyethylene pyrrolidone and 5 parts of polyethylene glycol.
4. The preparation method of the foamed aluminum acoustic panel for effectively reducing urban traffic noise according to claim 2, wherein the plasticizer comprises the following raw materials in parts by weight: 3 parts of dibutyl phthalate, 4 parts of dimethyl phthalate and 3 parts of diethyl phthalate.
5. The method for preparing the foamed aluminum acoustic panel for effectively reducing the urban traffic noise according to claim 2, wherein the adhesive is prepared from the following raw materials in parts by weight: 6 parts of starch, 6 parts of polyvinyl alcohol, 5 parts of polyurethane, 2 parts of butyl rubber, 3 parts of vinyl acetate resin and 4 parts of water-based organic silicon epoxy resin.
6. The preparation method of the foamed aluminum acoustic panel for effectively reducing urban traffic noise according to claim 2, wherein the foaming agent is prepared from the following raw materials in parts by weight: 3 parts of azodicarbonamide, 1 part of sodium bicarbonate, 14 parts of carbon black, 1 part of n-hexane, 2 parts of trichlorofluoromethane and 6 parts of sodium dodecyl sulfate.
7. The method for preparing foamed aluminum sound-absorbing panel for effectively reducing urban traffic noise according to claim 1, wherein the thickness of the aluminum plate body is 25mm, and the thickness of the foamed aluminum material adhered to both side surfaces of the aluminum plate body is 25 mm.
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