The Hyundai Motor Group is replacing a spot-welded steel structure with a one-shot plastic composite in the rear seat cushion frame in the Kia K9 luxury sedan, which will be known as the Kia Quoris when launched internationally next year.
According to Joel Myers, senior engineer at the Hyundai America Technical Center in Superior Township, Mich., this is the first time that the injection molding process has been applied to a completely flat rear floor structure.
The plastic used in the structure is long glass fiber high-crystalline polypropylene supplied by Honam Petrochemical of Seoul, South Korea. High crystallinity provides extra stiffness. Weight savings are estimated at 25% and cost savings are estimated at 10%. By saving weight on the frame, a smaller motor can be used, resulting in further savings. Wall thickness is close to 3 mm.
Myers said that the process can also be applied to the rear seat back frame. The composite frame will be used in the design of the next rear wheel drive sedan developed by Hyundai/Kia.
The frame is a finalist in the Society of Plastics Engineers Automotive Innovation Awards program. Winners will be announced at a banquet in Livonia, Mich. Nov. 7.
The frames are molded by Hyundai Dymos.
