Traverse City, Mich. — Toyota Motor Corp. has added more carbon fiber production capacity in house, and it's not just for supercars and not just about cutting weight.
The CF sheet molded compound it is making in Japan is used for the liftgate in its 2017 Prius Prime plug-in hybrid and in doors and deck lid for the Lexus LC.
Using carbon fiber SMC means the automaker can improve package space in the Prius, even with additional room needed for batteries, said J.P. Flaharty, executive program manager technical strategy department, Toyota North America R&D.
The composite also allows Toyota to make narrower rear pillars, so drivers have an improved sight line.
“We're looking for ways to benefit the customer that go beyond weight reduction,” Flaharty said in a July 31 interview at the Center for Automotive Research's Management Briefing Seminars in Traverse City. “It's also about the structure and the way we've executed the car: Better sight lines, better usability, better utility space.”
Toyota won the Altair Enlighten Award for its use of carbon-fiber reinforced plastics in the Prius and Lexus, presented during MBS. The parts represent a 40-50 percent weight reduction.
CF SMC is a new process for Toyota. The automaker has has used CF prepreg and resin transfer molding for its LFA supercar and high-performance variants of the Lexus IS and RC.
“Those are specialty use for those unique panels,” Flaharty said.
Working with material supplier Mitsubishi Chemical, the SMC process, with its chopped fibers rather than long fibers in prepreg and other processes, is both faster and has proved far easier for Toyota to bring in house, and in a mass market vehicle.
“One of the things I learned through the many discussion that I had is that the material we're using is more similar through design and manufacturing conceptually to sheet metal forming,” Flaharty said. “You're making a mold, you're making a shape, it's got this 3D characteristic to it, so we've got a lot of know how and a lot of understanding in how that works.
“We can align our capabilities to do this internally.”
Toyota assembles the Prius Prime at the Tsutsumi plant and the Lexus LC at the Motomachi plant, both near its headquarters in Toyota City, Japan.