Aluminum Foam for Tunnel

Ref Price:
Loading Port:
Payment Terms:
Min Order Qty:
Supply Capability:
50000 m²/month

OKorder Service Pledge

Quality Product

Order On-line Tracking

Timely Delivery

OKorder Service Pledge

Credit Rating

Credit Services

Credit Purchasing

Share to:

Product Description:

Product Description

 100% Recycling Soundproofing Closed Cell Aluminum Foam Panel


Characteristics of noise inside tunnel

The noise generated and will bereflected from inner walls of tunnel into the vehicle interior walls when carsor trains pass through the tunnel, the situation of which gets passengers intoextremely harsh noise environment. Not only that, the air at entrance of tunnelwill be formed as pressure and transported to the tunnel exit as soon asvehicles enter the tunnel, the noise formed by compressed air in the exhaustoutlet at breakneck speed will have a great impact power, which might be agreat damage to nearby residents.

According to the characteristics ofnoise existing inside the tunnel, a special voice control system designed andproduced in the material of aluminum foam made by our company. The system iscurrently the most advanced voice solutions for tunnel. (Note: we’ve appliedfor an international patent already)

Generation of noise inside tunnel

1.     Characteristics of noise inside tunnel

   Air-Borne Sound: vehicles movinginside tunnel

   Structure-Borne Sound: vehicles movinginside tunnel

2.     Characteristics of noise at the exitof tunnel

   Reflection of noise inside tunnel

Thedensity of noise power is very high; Floors and walls inside tunnel are formedentirely reflective, the noise shall be getting into the vehicles strongly ortransformed to the exit of tunnel

   Impact noise generated due to pressurechanges

⊙Pressure wave formed at the entrance of tunnel when entering the tunnel

⊙Rapid release of the compressed air pressure wave when it’s reaching to theexit of tunnel

⊙ Agreat impact noise formed

⊙Impact noise changes together with different shapes of tunnel entrance

Noiseof train                                      

Transmissionnoise: noise formed by friction of wheel and rail                        

Airnoise: noise formed in the moving process of train                              

Othernoise: noise made by inner equipments of train

Noiseof normal vehicle (cars and trucks)

Frictionnoise: noise formed by friction of wheel and ground

Airnoise: noise formed in the moving process of vehicles

Othernoise: noise made by engines and other inner equipments                                          

Tunnelinternal noise standards with the materials selected

1.     Shall be incombustible material

In order to prevent secondary disasteras soon as vehicles crush happens

2.     Shall be non-toxic material

Chemical materials shall not be usedas sound-absorbing material, which is in order to avoid toxic gases go out assoon as fire disaster happens

3.     Shall not cause dust and secondarypollution

The sound-absorb effect of glass wooland other kinds of rock wool products continues to reduce, carcinogen dust andfine particles from which will give a great damage to human health

4.     Shall use environment protectionproduct

Convenient for transporting andconstructing, possibly to do recycle

5.     Shall be cleaned by water

Piling of dust and soil inside tunnelshall be cleaned up by using high pressure water regularly, which is to makesure the effect of sound-absorbing; the characteristic of anti-water requiredto be satisfied with sound-absorbing material

6.     Shall be used for a long period

Glass wool and other rock wool can notbe used for long time because its self-weight, the sound –absorbing effectcontinues to reduce too, but for the using period of aluminum foam could reachto more than 30 years

7.     Shall bear high wind pressure

Making installation rugged durabilityby accurately calculating

Adjustablein accordance with the design specifications and size of tunnel

Installation method ofsound barriers in tunnel.

1. Markthe keel beam installation position inside tunnel

2. Installand fix the keel beam in the tunnel

3.The distance between two keel beams is 500-600m

4.Install Aluminum foam sound-absorbing panel

5. Inset Aluminum alloy frame in orderto fix the Aluminum foam panel

6. Fix it to the beam with bolts

7. In order to prevent the boltsfrom loosening, install sturdy nuts.


1. Materials used inside the tunnel mustbe stainless steel or aluminum.

2. The specification of Aluminum foamsound-absorbing panel is adjustable as the design of the tunnel

3.Color of Aluminum foam sound-absorbing panel can be customized as required.

What is AluminumFoam?

Aluminum foam is a new concept metalmaterial which is foamed in sponge shape after melting aluminum ingot with various chemical ingredients and has many bubble layers inner structure.

Porous material is much lighterthan original one, which is the characteristic of porous. And, it improves the ability of  energy absorption and reduces the abilityof thermal and electrical conductivities than original metal materials. Inaddition, porous material has wide applications as well as excellent ability ofsound absorption and permeability of liquid, air, etc.

Aluminumfoam, a metal itself, can be applied to aerospace aviation required the  thermostability over 200℃. It is a 100%  recyclabl ecofriendly material and absolutely will not produceharmful substances no matter in the process of producing,  using or abandoning.

Main properties of aluminum foam


Density is 0.2~0.4g/cm3 (Aluminium1/10,Iron1/30, and Wood 1/4)


Porous structure has a good soundabsorption.

Aluminum foam sound-absorbing materialcan be used in the inner decoration of buildings (walls, ceiling and floor),railway, highway, factories, mechanical equipment and any other fields.

Suitable for noisy place.


100%non-flammability and no toxic gas released when burning.

Non-combustibility TEST verified to be qualified. <KIMM; IMO A.799 (19)>

I grade Non-flammability TEST ofaluminum foam surface verified to be qualified. <KICT; KS F2271>


Porous structure can effectively absorbenergy.

Have a great effect on energyabsorption after a high impact.

Firstly acquired the national SB5class (Guard rail shock-absorber)

Electromagnetic wave shielding ability

Aluminum foam has a function ofabsorbing electromagnetic wave

Widely used in military (stealth materials),TV station, hospital and any other electromagnetic shielding places.


100% recyclable Aluminum foam is nonpoisonous, odorless andharmless, no toxic gas released when burning.

Aluminum foam can be produced by recycled aluminum andits scraps.



Aluminum foam composed panel

Aluminum  honeycomb plate





Aluminum plate(GRP plate)

aluminum foam

aluminum plate(GRP plate)

Aluminum plate(GRP plate)

aluminum honeycomb

aluminum plate(GRP plate)

Waterproof performance

long time  immersion and corrosion in water)

Excellent(oxidized pure metal)

Excellent but easy to rust

Fireproof performance


(Non-flammability of pure metal)

General (Glue layer in the middle is not resistant to  high temperature)

ComparisonAluminum Foam with Other Sound-absorbing Materials


Aluminum Foam


Glass Fiber

Urethane Form





SiO2, mineral

high molecular Material

Acoustic absorption(NRC Standar d)

over 0.70

over 0.70

over 0.75

over 0.65

Long-term sound absorption


Property is decreased

Property is decreased

Property is decreased


100% recyclable Eco-friendly

No recyclable, flammable, produce  little dust

No recyclable, no flammable, arsenic acid cause gas  pollution

No recyclable and flammable

Materials handling & Constructability

Easy handling, using and working under no protective  equipment

No damage when handling and using, easy to work under no  protective equipment

Low stability. Easy to cause  respiratory disease and skin ailments when touching

No damage when handling and using, easy to work under no  protective equipment

Human harmfulness




Poisonous gas (CO, Cyan gas) release when burning

Waterproofness & Sound  absorption

Waterproofness is  excellent , stable form, permanent sound absorption

Waterproofness and  adhesion is good, stable form

Absorb moisture and poor drainage cause lower acoustic  absorption

Absorb moisture and poor drainage cause lower acoustic  absorption


grade Non-flammability
 -under 780℃


 -under 350℃

Easy flammable
 -under 100℃

Send a message to us:

Remaining: 4000 characters

- Self introduction

- Required specifications

- Inquire about price/MOQ

1. Manufacturer Overview

Year Established
Annual Output Value
Main Markets
Company Certifications

2. Manufacturer Certificates

a) Certification Name  
Validity Period  

3. Manufacturer Capability

a)Trade Capacity  
Nearest Port
Export Percentage
No.of Employees in Trade Department
Language Spoken:
b)Factory Information  
Factory Size:
No. of Production Lines
Contract Manufacturing
Product Price Range