China Chemical Instrument Network

U.S. scientists have used helium and indium alloys to develop such liquid metals that can change shape and repair themselves. The melting point of bismuth is 29 degrees Celsius; the melting point of indium is as high as 156 degrees centigrade. However, when the two are "married", the resulting alloy is liquid at room temperature and has a high surface tension. This means that when the alloy is placed on a smooth table, it will form an almost perfect ball, and keep its shape unchanged. Applying a voltage of less than 1 volt can reduce the surface tension, causing the liquid metal to stretch over the surface. Moreover, this effect is reversible, if the voltage is switched from negative to positive, the liquid metal will return to a spherical shape. In addition, changing the voltage can also change the surface tension and the viscosity of the metal cluster, so that it can be transformed into a different structure.

Michael Dickney, an associate professor at the University of North Carolina State, who co-authored the study, said that using surface voltages less than 1 volt can make such surface tensions change so dramatically. It's amazing. This breakthrough may help people develop better circuits, self-healing structures, and even T-1000 type robots. He said: "We can use this technology to control the movement of liquid metal, so that we can change the shape of the antenna and make the circuit connected or disconnected."

Researchers also said that this study may be used to repair damaged nerves in the human body and prevent long-term inconvenience. When the nerves are damaged, the muscles at one end of the nerve and the signals from the brain are cut off, so the muscles will solidify and may cause the muscles to shrink.

In order to prevent weakening of nerve function during muscle atrophy, nerve signals need to be sent out from the brain during nerve repair, and transmitted to the muscles through gaps between damaged nerves. The most common way is to use a compound sodium chloride solution that can replicate body fluids, but scientists say that liquid metal may be able to transmit signals better.