TOKYO -- Hitachi Metals aims to create a new aluminum-carbon composite for automobiles that is 60% lighter than steel and less expensive than typical carbon fiber composites.
The Japanese company will begin the effort at a new R&D facility to be launched next spring. It hopes to have a practical version of the material ready in 2025 for use in suspensions and other structural parts of a car.
The new material is a composite of aluminum and carbon nanotubes. Corrosion at joints is a problem with this kind of composite because aluminum and carbon are incompatible, but Hitachi Metals is on the road to solving this problem with casting technologies relating to joining and surface processing.
Because the new aluminum-carbon composite can be made on existing machinery, it can be mass produced more cheaply than other carbon fiber-based composites.
Cost is the key when it comes to automotive materials. Structural parts like suspensions currently are made using either high-tensile steel, aluminum alloys, or carbon fiber composites. Aluminum is far lighter than steel, but weaker. To make them stronger, producers give aluminum autoparts thicker, more complicated structures. Carbon fiber composites are light and strong but very expensive to make.
Hitachi Metals will promote the new material as an intermediate choice in terms of strength and cost between aluminum and carbon fiber composites.
The company anticipates growing demand for lightweight automotive materials as fuel efficiency regulations stiffen. Widespread use of self-driving vehicles is also expected to boost the demand, since equipment to realize autonomous driving adds to the vehicle weight.