Porosity refers to the ratio of the volume of all pores in a porous body to the total volume of the porous body, and often measures the size of the void space of the porous body. The metal foam often has a porosity of more than 90-95% and a porous metal having a certain strength and rigidity. These metals have high porosity and pore diameters up to the millimeter scale.

Ni foam is a kind of metal foam. metal foam also has lead metal foam , Cu metal foam, Ti metal foam, etc. metal foam is also called sponge metal. It has high porosity, large specific surface area and unique three-dimensional network structure. Metal. Metal foam plays an important role in the fields of absorbing, filtering, catalyzing, and energy storage. One of the main varieties of metal foam is Ni metal foam. Before the sponge substrate is plated with metallic Ni, the sponge is subjected to a conductive treatment. One of the processes of the treatment is that the sponge infiltrates the conductive adhesive to make the sponge conductive, and then the Ni ions are electroplated onto the sponge substrate, and the Ni metal foam is formed by a process such as baking, reduction, and the like. One type of conductive adhesive used in the above process is an aqueous graphite emulsion which meets the requirements of Ni metal foam production, and the use of water-based graphite emulsion as a conductive adhesive reduces the environmental pollution caused by the production of Ni metal foam. The high-performance Ni metal foam produced by the sub-micron graphite milk with specific properties has the characteristics of high porosity, low electrical resistance, good folding resistance and large specific surface area.

Application field of metal foam Metal foam is a product of modern structural material research. It has been widely used in aerospace, petrochemical, environmental protection and other fields now due to its excellent sound insulation, heat insulation, gas permeability and excellent impact energy absorption performance. A car made of a foam material not only enhances the safety of the collision buffer, but also effectively reduces the weight of the car and improves fuel efficiency. The bullet-proof vests developed by the composite metal foam can be easily resisted by the special ceramic slabs, and the armor-piercing bullets with a speed of more than 3,000 kilometers per hour can be easily used. The armor of some warships is even made of foam metal materials, so the application prospect of the foam metal is self-evident. Metal Foam are currently widely used in the main types of nickel foam, copper foam, aluminum foam, Titanium Foam, Graphene Foam,Etc. They are mainly used to manufacture automobile bumpers, electromagnetic shields, fluid filters, electromechanical shock absorbers, and the like. Metal foam as an emerging material, its development space can be said to be limitless, so the research and testing of foam metal is particularly important. the mechanical properties of foam metal are the key to the performance of foam metal materials.