Traditionally, auto manufacturers have used aluminum, carbon fiber and specialized steel to construct their cars and make them as lightweight as possible. These materials are usually recycled at the end of their lives.
These materials offer a combination of strength and a lightweight structure. Less weight, of course, when it comes to a vehicle, means it can travel that much faster.
However, researchers in Kyoto, Japan, have discovered a new material that vehicles could be constructed from in the future that has many of the same properties as traditional materials used to construct cars.
The material is called cellulose nanofiber, and it’s made primarily from wood pulp. It’s one-fifth as heavy as steel and can be five times stronger. These researchers, located at Kyoto University, are hoping it can become something that’s useful and affordable by 2030.
Denso Corp, who is Toyota’s biggest supplier of materials used to construct vehicles, the researchers are collaborating with them to experiment with mixing cellulose nanofibers with plastic. This wood pulp material is made from breaking down wood pulp into minuscule sizes, or one thousandth of a millimeter.
These materials have been used in other industries, such as the medical field, in the healthcare industry and electronics, and the Kyoto researchers see big potential for their application in constructing vehicles. Their high surface area, small pore size and other benefits make them favorable for combining with other materials to create vehicle parts. In the procedure devised by the Kyoto researchers, the individual wood fibers are folded into the plastic material while at the same time are broken down into nanofibers. This would help reduce production costs as well.
These cellulose nanofibers would also have applicability to aircraft parts, as a lightweight structure for planes, which rely on a lightweight structure to function properly.
Despite these numerous benefits for using them in constructing vehicle parts, it likely won’t be seen on production lines for many years. Automakers would have to completely revamp their assembly lines, and costs would also need to come down for producing parts with the cellulose nanofibers.
According to the team at Kyoto University, it currently costs approximately $9 (1,000 yen in Japan) to mass produce a kilogram of cellulose nanofiber. On the other hand, to produce the same amount of aluminum and steel costs about $2. The difference in cost alone is enough to make most automakers hesitant, so further work still needs to be done to streamline the process and somehow find a way to bring costs down.
By 2030, these researchers hope to greatly reduce prices for producing cellulose nanofibers in half. It would make it much more competitive compared to other materials because it can be combined with plastic. Carbon fiber prices, comparatively, are also expensive. In the year 2025, it’s expected their prices will be around $10 per kg, making it about the same price as the current estimates for cellulose nanofibers.
In order to convey the many benefits of this material, researchers are currently working on a prototype vehicle that would be constructed using this material, and they expect to be finished with it by 2020.
The cellulose nanofibers may have other vehicle-related applications as well. One group in the UK is working on testing roads made from recycled plastics that are said to be stronger and longer lasting than traditional asphalt roads. Perhaps in the future, some roads could be made with this cellulose nanofiber material.
One thing is certain, for now — so long as humans continue to innovate and come up with new solutions for old problems (manufacturers tried to make vehicles lightweight in order to make them faster for as long as anyone can remember), new inventions and materials will always arise. Only time and more research will dictate whether or not the use of cellulose nanofibers takes off in the future. Researchers are hoping it does, as it would revolutionize the way that lighter car parts are manufactured and make the process much more sustainable.