Chinese people's creativity is often ignored by the public, in the new generation of heat dissipation technology, the physical and chemical technology, the director of the low-temperature biological and medical lab of Chinese Academy of Sciences, Liujing and his team completed a remarkable job.
Their developed the new-generation liquid metal which is a typical representative of the excellent material. The coefficient of thermal conductivity is 60 ~ 70 times of water, the capacity of trapping heat is much stronger than water. You must know, the boiling point of liquid metal is as high as 2000 „, the ability of fighting against extreme temperature is very outstanding.
Liquidmetal and Vitreloy are commercial names of a series of amorphous metal alloys developed by a California Institute of Technology (Caltech) research team and marketed by Liquidmetal Technologies. Liquidmetal alloys combine a number of desirable material features, including high tensile strength, excellentcorrosion resistance, very high coefficient of restitution and excellent anti-wearing characteristics, while also being able to be heat-formed in processes similar to thermoplastics. Despite the name, they are not liquid at room temperature.
Liquidmetal was introduced for commercial applications in 2003. It is used for, among other things, golf clubs, watches and covers of cell phones.
The alloy was the end result of a research program into amorphous metals carried out at Caltech. It was the first of a series of experimental alloys that could achieve an amorphous structure at relatively slow cooling rates. Amorphous metals had been made before, but only in small batches because cooling rates needed to be in the millions of degrees per second. For example, amorphous wires could be fabricated by splat cooling a stream of molten metal on a spinning disk. Because Vitreloy allowed such slow cooling rates, production of larger batch sizes was possible. More recently, a number of additional alloys have been added to the Liquidmetal portfolio. These alloys also retain their amorphous structure after repeated re-heating, allowing them to be used in a wide variety of traditional machining processes.
Liquidmetal alloys contain atoms of significantly different sizes. They form a dense mix with low free volume. Unlike crystalline metals, there is no obvious melting point at which viscosity drops suddenly. Vitreloy behaves more like other glasses, in that its viscosity drops gradually with increased temperature. At high temperature, it behaves in a plastic manner, allowing the mechanical properties to be controlled relatively easily during casting. The viscosity prevents the atoms moving enough to form an ordered lattice, so the material retains its amorphous properties even after being heat-formed.
The alloys have relatively low softening temperatures, allowing casting of complicated shapes without need of finishing. The material properties immediately after casting are much better than that of conventional metals; usually, cast metals have worse properties than forged or wrought ones. The alloys are also malleable at low temperatures (400 °C or 752 °F for the earliest formulation), and can be molded. The low free volume also results in low shrinkage during cooling. For all of these reasons, Liquidmetal can be formed into complex shapes using processes similar to thermoplastics, which makes Liquidmetal a potential replacement for many applications where plastics would normally be used.
Liquidmetal combines a number of features that are normally not found in any one material. This makes them useful in a wide variety of applications.
One of the first commercial uses of Liquidmetal was in golf clubs made by the company, where the highly elastic metal was used in portions of the face of the club. These were highly rated by users, but the product was later dropped, in part because the prototypes shattered after fewer than 40 hits. Since then, Liquidmetal has appeared in other sports equipment, including the cores of golf balls, skis, baseball and softball bats, and tennis racquets.
The ability to be cast and molded, combined with high wear resistance, has also led to Liquidmetal being used as a replacement for plastics in some applications. It has been used on the casing of late-model SanDisk "Cruzer Titanium" USB flash drives as well as their Sansa line of flash-basedMP3 player, and casings of some mobile phones, like the luxury Vertu products, and other toughened consumer electronics. Liquidmetal has also notably been used for making the SIM ejector tool of some iPhone 3Gs made by Apple Inc., shipped in the US. This was done by Apple as an exercise to test the viability of usage of the metal. They retain a scratch-free surface longer than competing materials, while still being made in complex shapes. The same qualities lend it to be used as protective coatings for industrial machinery, including petroleum drill pipes and power plant boiler tubes.