A team of scientists at Boston-based Northeastern University has developed a new type of glue that could soon replace welding and soldering. Currently the two most common methods for joining metal components together, both soldering and welding rely on the use of heat, and usually come with their own set of risks, including the possibility of damaging intricate electrical pieces, or even starting a fire. Often times, the improper application of heat results in defects and voids in the materials being fused. The new substance, known as MesoGlue, acts like a conductive material that effectively joins two metal parts together, at room temperature.
According to the researchers, MesoGlue contains two specific nanorods, each with a special metallic core. Of these, one possesses a gallium coating, while the other has indium. When applied to the metal pieces, the nanorods stir up straight like the bristles of a brush. To fuse the two surfaces, one needs to press the mixture together, applying a small amount of force to facilitate the bonding process. Speaking about the research, recently published in the Advanced Materials & Processes journal, Paul Elliott, a Phd student at Northeastern University, said:
When you mash the heads of the brushes together, all the little bristles push past each other so the two brushes are basically stuck together. The interlacing process is fairly similar in our glue. The bristles are spaced well enough so they can slide or be pressed in between each other.
As the team points out, the new material works similar to Velcro, with the two nanorods interlocking to form an inseparable bond. Unlike Velcro, however, MesoGlue will never come apart, once set. Pressing the nanorods actually brings the gallium and indium layers close together, which in turn results in the creation of a special liquid film that then fills the space between the two microscopic rods. Reaction between the film and the nanorods’ metallic cores causes it to solidify, thus fusing the metal object together. The entire process differs from soldering and welding, in that it uses zero external heat.
Laboratory testing has revealed that the bond created by MesoGlue is nearly as strong as a conventional weld. What is more, the fused material remains electrically and thermally conductive, same as what happens in case of welding and soldering. When used as a substitute of these two methods, the newly-developed substance could eliminate defects that usually occur when delicate electrical components are soldered together, and could also help miniaturize circuit boards. The team added:
The metallic glue has multiple applications, many of them in the electronics industry. As a heat conductor, it may replace the thermal grease currently being used, and as an electrical conductor, it may replace today’s solders. Particular products include solar cells, pipe fittings, and components for computers and mobile devices.
The scientists believe that the technology could actually prove useful in the production of solar panels and processor thermal compounds with uniform heat dispersal. While the glue currently exists only inside the laboratory, a spin-off company is working to create a liquid version that can be easily used at home.
To know more about MesoGlue, click here.
Source: Northeastern University