Molded, Hybrid Composite Creates Tough Truck-Mounted Toolbox

SABIC has collaborated with Dongfeng Motors, one of the largest truck manufacturers in China, on the development of a plastic composite hybrid design for a strong, lightweight truck-mounted toolbox. The application combines SABIC’s Stamax long-glass-fiber polypropylene (PP) and continuous-glass-fiber composite laminate inserts via a single overmolding process. The resulting part is up to 30% lighter than a comparable designed part in steel and results in production efficiencies, according to SABIC.

The thermoformed composite inserts are supplied by China’s Qiyi Tech and composed of unidirectional (UD) glass fiber-reinforced PP tape. A SABIC spokesperson told Plastics Technology that the two inserts for this application, which are 2.5-mm thick, are preheated to 230 C prior to molding in a 1500-ton press, with the overmolding process running an 80-sec cycle. SABIC notes that the inserts add stiffness and strength to critical areas of the part, enabling the use of thin-wall geometries that reduce overall weight.

Compared to steel typically used in truck toolbox applications, SABIC says its plastic composite hybrid expands design options, consolidates parts, and eliminates secondary operations that can add costs and prevent high-volume production.

The plastic composite toolbox weighs 4 kg, down from 6 kg, but doesn’t sacrifice the stiffness, toughness, or strength required for this utility application. SABIC notes that its Stamax resins feature 10 to 25% lower density than some competitive materials, further cutting application weight. The material’s properties include high stiffness and impact strength, good structural performance, and easy flow allowing thin walls.

In addition to truck toolboxes, automotive applications for this hybrid solution could include tailgates, seating, front-end modules and battery housings for electric vehicles.