Foam magnesium alloy-Electromagnetic shielding material

Porous magnesium alloy foam magnesium alloy is also called the sphere open groove foam magnesium alloy holes distributed, in part by a bubble of tank and tank wall small round hole, equivalent to use multiple hollow ball hollow out closely the accumulation of the dense magnesium alloy, formed to allow the electromagnetic waves, sound waves, gas or liquid substances in the magnesium alloy flow through space, therefore, also called metal sponge foam magnesium alloy.

The bubble chamber of the spherical opening type foam magnesium alloy is spherical, relatively regular, and each sphere is arranged very closely with each other. Small round holes are cut in each bulkhead wall to connect other spheres, going to 6 directions, and the connectivity rate is more than 90%.The structure of the sphere connected by the pores is conducive to the absorption and filtration of energy. Since there is no straight hole, the energy passes through the repeated conversion between the sphere and the pores, and the flow rate and velocity will undergo a gradual attenuation change.

For electromagnetic shielding, the spherical through - hole foam magnesium alloy circular hole network structure can effectively shield electromagnetic waves.This is because the free electrons in the metal round hole in the electric field under the action of electric field, directional movement, round hole net creates a free electrons to form internal electric field, electric field inside a circular aperture is outside under the action of electric field, a constant when the electric field reaches a certain value, the internal electric field and electric field is equal and opposite direction, so that various points inside the metal round hole within external electric field and electric field vector and is 0, that is the electrostatic shielding.The magnetic field will not cause the electrons to move in the direction of the conductor, there will be no potential difference on the conductor, so the magnetic field will not have no effect on the static conductor, which will not cause the metal to produce a counteracting force against the magnetic field.

For sound absorption and noise reduction, the ideal application effect can be obtained through the design and process control of the size of the ball (5-1mm in diameter), the size of the wall hole, the thickness of the hole wall and the thickness of the plate.Bulk density: about 0.6g/cm?.The noise reduction coefficient of the foam magnesium alloy exceeds the international standard, and it is the top product of the sound absorbing material in China. It is suitable for noise reduction of the box of various delivery vehicles and mechanical equipment.

For anti-impact energy absorption, the circular compact stacking structure has incomparable advantages: spherical bubble chamber, round wall hole and bulkhead are relatively regular, so that the spherical open hole is more resistant to energy absorption and anti-impact.Compared with the closed cavity produced by gas foaming and slow release foaming method, the buffer time is longer and the rebound is not recovered when the shock energy is received.Compared with other types of metal foam, the ball opening type has much higher compressive strength (44MPa) and bending strength (30MPa), which is significantly improved.

 Compared with the traditional ferrite shielding material, its performance is improved by 30 times, and its heat dissipation performance is very good.Suitable for making military command vehicle, radar control system, command post and other protective lining, can effectively resist electromagnetic bombs and other high power electromagnetic signals.It has a broad market in power stations, military equipment and other fields.

At present, the size of laboratory samples is 1mm-5mm with a density of 0.5-0.8g/cm., thickness 8mm-50mm, area 30cmX50cm, damping coefficient 0.0589.Can withstand high temperature of 300 degrees Celsius, sound frequency between 125-2000Hz sound absorption coefficient can reach 0.98, noise reduction coefficient of more than 0.4, electromagnetic frequency between 2.6-18GHz, electromagnetic shielding in 80-90dB, resistivity is 100 times of pure magnesium. Also good corrosion resistance, good weather resistance, low moisture absorption, no aging, no toxicity, can be used in various fields of industrial production.