In 2015, metal matrix composite foam materials were jointly developed by researchers from DST and New York University Institute of Technology.
It has a density of only 0.92 g/m3 and can float on water. Surprisingly, this material has satisfactory strength while achieving light weight, and its single spherical shell can withstand a pressure of 25,000 pounds per square inch before breaking. Compared with traditional metal foam, the advantage of metal-based composite foam is that the density can be customized within a certain range, and the size and shape of the holes can also be controlled.
Metal Foam Porosity
Porosity refers to the ratio of the volume of all pores in a porous body to the total volume of the porous body, it is a regular measurement of the void space of a porous body. The porosity of foam metal normally reaches more than 90%, and it is a porous metal with certain strength and rigidity. This kind of metal has high porosity, and the pore diameter can reach the millimeter level.
The density of metal foam makes metal foam materials have special applications. For example, The metal foam materials used in the field of automobile manufacturing, it can reduce vehicle weight, improve fuel efficiency, and maximize the protection of passengers in the event of an accident with the helps of good energy absorption ability.
In actual production, it was discovered that many auto parts can be made of foamed aluminum. Such as top cover, bottom cover, seats, bumpers, front and rear longitudinal beams, etc. For example, the roof panel made of sandwich foam aluminum from Kaman Automobile Company of Germany has a stiffness about 7 times higher than that of steel components, but its weight is about 25% lighter than steel components.
Reference: The development history of metal foam
In 1948, Sosnik proposed the preparation of metal foam aluminum alloy with vaporized mercury, which marked the first time that human beings had the concept of metal foam. meanwhile, it broke the long time traditional theory that metals only have dense structure.
In 1951, Elliott successfully produced foamed aluminum by melt foaming method.
In 1983, the paper published by G.J.DVIES marked the official start of the research on metal foam system, and the researching on metal foam started with an active period.
In 1988, 《Porous Solids-structure & Properties》 published by L. J. Gbson & M.F. Ashby is still an important work in the field of porous materials research.
In 1991, Kyushu Industrial Research Institute of Japan has developed an industrial process for the industrial production of foamed aluminum.
In 2000, Ashby and his team firstly systematically summarized the preparation method, performance and application direction of metal foam.
Since 2000, the preparation technology of fine particles has gradually matured, and the research field of metal foam has also begun to develop rapidly.