Take a look at the preparation methods and application areas of foamed metals

Preparation of Foamed Metals 
1. Gas Injection Foaming Method 
Normally, pure liquid metals are not easily foamed by gas injection, because the bubble wall draiNing process is rapid and there is not enough bubble stabilization time for solidification to form a porous body. However, viscosity enhancers such as ceramic particles (silicon carbide or zirconium oxide) can be added to impede gas drainage from the liquid metal and stabilize the foaming process. This method is extremely well suited to the low melting point, non-oxidizable metal aluminum. Many gases can be used for foaming, air is the most commonly used, but also carbon dioxide, inert gas, etc.
2. Powder densification foaming method 
This method is to mix the metal powder and blowing agent evenly, then the mixed powder is made into a prefabricated foaming body by extrusion, hot isostatic pressing or powder rolling, etc., and then the panel material is processed with the prefabricated foaming body to form the pre-foamed foam metal sandwich panel. This method is mainly used for the preparation of foam metal sandwich panels, or foam metal shaped parts with complex shapes.
Foam metal applications 
1. Aerospace 
 In the aerospace industry, the weight and performance of materials are extremely demanding. The low density and high strength properties of foam metal make it an ideal material for manufacturing aircraft components. It can be used in the manufacture of aircraft wing metal shell support bodies, the missile nose cone of the high-temperature collapse of the shell to prevent the support body, as well as the landing gear of the spacecraft and so on. The use of foam metal can not only reduce the weight of the aircraft, and improve fuel efficiency, but also enhance the strength and stability of the structure to ensure flight safety.
2. Automobile industry 
In the automobile industry, foam metal also has a wide range of applications. Such as automobile bumpers using foam metal, can effectively absorb energy in collision, reduce the impact on the body, to protect the safety of passengers in the car; foam metal can also be used for automobile sound insulation and noise reduction, to improve the comfort of the car; In addition, due to the light quality of the foam metal, used in the automobile manufacturing can reduce the weight of the body, reduce energy consumption, in line with the development trend of energy saving and emission reduction of the automobile industry.
3. Construction field 
In the construction field, foam metal can be used to make light, hard, fire-resistant elements, railings, or the support body of these things. The high-frequency and high-speed acceleration and deceleration of modern elevators especially require lightweight structures like foam metal with both energy-absorbing and load-carrying properties to reduce energy consumption. At the same time, the acoustic properties of foam metal make it a good choice for soundproofing in buildings, effectively reducing the transmission of noise from inside and outside the building.
4. In the field of electronic equipment 
With the continuous development of electronic equipment, the performance requirements for materials are getting higher and higher. Foam metal has good electromagnetic wave absorption ability, and can be used to make electromagnetic shielding components of electronic equipment, to prevent electromagnetic interference between electronic equipment, and to ensure the normal operation of the equipment. In addition, foam metal can also be used for heat dissipation of electronic devices to improve the stability and service life of electronic devices.
5. Biomedical field 
In the biomedical field, foam metals also show a unique application potential. For example, foamed metals can be used for the preparation of artificial bone, depending on the requirements of a pore size of 150 - 250 μm and a high porosity. This type of foam metal can withstand certain loads during molding and other processes as well as in the human body, maintaining high mechanical properties while achieving the large porosity required for human bone, which can help to promote the growth and healing of bone tissue and reduce the body's rejection of the implant.
As a new type of material, foam metal, with its unique structure and excellent performance, has shown great application value and development potential in many fields. It is believed that shortly, metal foam will come into every aspect of our lives, bringing us more surprises and convenience.