Teijin
Limited has established the world’s first mass production technologies
for carbon fiber reinforced plastic (CFRP), achieving a significant
reduction of the cycle time required for molding automobile cabin frame
to less than one minute. The breakthrough overcomes one of the biggest
challenges in the industry and represents a long stride toward the use
of carbon fiber for the mass production of automobiles and other
products.
Teijin’s
new technologies include intermediate materials made of thermoplastic
resin instead of conventional thermosetting resin for molding-use CFRP.
Teijin also developed technologies for welding thermoplastic CFRP parts
together and for bonding CFRP with materials such as steel, both of
which will help to reduce the use of metal in manufacturing processes.
Going
forward, Teijin intends to develop mass production applications for
CFRP in automobiles and many other items that require certain levels of
structural strength, such as machine tools and industrial robots.
New intermediate materials
By
impregnating carbon fiber with thermoplastic resin, Teijin developed
three intermediate materials for the production of CFRP suited for use
in mass-production vehicles. The materials can be used selectively
depending on the required strength and cost of the part, and they can be
made with various thermoplastic resins, including polypropylene and
polyamide. The new intermediate materials are as follows:
- Unidirectional intermediate: ultrahigh strength in a certain direction.
- Isotropic intermediate: optimum balance of shape flexibility and multidirectional strength.
- Long-fiber thermoplastic pellet: high-strength pellet made from carbon fiber, suited for injection molding of complex parts.
Using
these new intermediate materials, Teijin developed its new technologies
for the press molding of CFRP within one minute’s time. The technology
also is simpler than conventional methods. In addition, Teijin developed
technologies for welding thermoplastic CFRP parts together, and also
for bonding CFRP with materials such as steel.
Electric-vehicle concept car
To
demonstrate its new technologies, Teijin has developed an
electric-vehicle (EV) concept car that features a cabin frame made
entirely from thermoplastic CFRP and weighing only 47 kg, or roughly one
fifth the weight of a conventional automobile’s cabin frame. The
four-seat EV, which is capable of speeds up to 60 km/hour and has a
cruising range of 100 km, embodies Teijin’s vision of super-lightweight
EVs made with CFRP.
Teijin
will use the concept car to introduce its technologies to automakers
and parts suppliers, and also to promote joint initiatives to develop
lighter automobiles. Teijin also aims to establish new midstream and
downstream business models for its carbon-fiber composites business by
supplying CFRP parts to the market.
The
Teijin Group, which has positioned automobiles and aircraft as one of
its key growth markets, has been developing CFRP for such applications
through collaboration between the Teijin Composites Innovation Center
and Toho Tenax (http://www.tohotenax.com/tenax/en/), the core company of
the group’s carbon fibers business.
Conventional
CFRP utilizes thermosetting resin and requires at least five minutes
for molding, so it is not suited for mass production applications that
require molding within about one minute, such as the production of
general-purpose automobiles. This is why CFRP has been limited to use in
high-end vehicles.
Looking
ahead, the Teijin Group aims to accelerate its expansion of advanced
composite materials, one of the pillars of the group’s long-term growth
strategy. To this end, Teijin will establish on April 1 a new business
group, named the Carbon Fibers and Composites Business Group, by
integrating its current business units for carbon fibers and composite
materials.