We recently caught up with Mathieu Boulander, VP of Business Development at molding process developer RocTool. The company recently announced the addition of overmolding to its Integrated Internal Induction Technologies (3iTech) for forming mixed composite and plastic parts. Introduced in 2009, 3iTech uses induction to locally heat the surface of a magnetic steel mold. Heating a smaller volume makes it more practical to operate at higher temperatures, enabling faster cycle times, improved surface quality, and thinner parts, while eliminating the need for preheating and pre-consolidation. The new “hybrid” technology is a two-step process: a thermoplastic composite is compression-molded and an unfilled plastic is subsequently injection-overmolded. The result is a multi-material part that does not need to be trimmed or surface-finished.
RocTool faces a few strong competitors in this emerging area: FiberForge’s (Client registration required) automated tape-laying system has a long list of existing technology partners, heavyweight Teijin has incorporated a proprietary welding process (Client registration required), and Cutting Dynamics’ unique hydroforming process is also notable. However, each uses either thermoforming, pressure forming, or hydroforming – processes limited in design capabilities when used alone. RocTool’s integrated overmolding greatly expands design flexibility, while maintaining reasonable cycle times of two to four minutes; and the company’s 40 licensees – including Flextronics, SABIC (Client registration required), Engel, and Azdel – are evidence that the composites industry considers these benefits desirable and cost-effective. The one caveat is that the finished part will not entirely be continuous fiber-reinforced composite, which could mean cost savings for some applications but reduced performance for others. Although consumer electronics is currently its primary application focus, BMW has been a partner since 2005, and the improved cycle times and design flexibility offered by RocTool’s novel process technology may help it find further traction in automotive lightweighting (see the report “Under the Hood: Mapping Automotive Innovations to Megatrends.” Client registration required).