Polyamide die-cast metal replacement grades launched

DSM is once again extending its range of ForTii high performance polyphthalamides based on polyamide 4T. Following the introduction earlier this year of the ForTii Eco family of partly bio-based grades, it is now launching the ForTii MX grades to provide a more cost-effective alternative than ever to die-casting metals.

DSM sees potential for ForTii MX in structurally loaded parts such as housings, covers and brackets found in the automotive powertrain, air and fuel systems, the chassis and the suspension, as well as in industrial, pumps, valves, actuators, home appliances and fasteners.

Plastics have been gradually replacing metals in applications across consumer and industrial markets, especially automotive, for many years. But the potential for replacing die-cast metal parts still remains enormous. The market around die cast replacement is currently growing at close to 10% per year. DSM believes that the increasing availability of high performance materials like ForTii MX will ensure that high growth continues and possibly increases well into the future.

ForTii MX grades, which like all ForTii types from DSM are partially aromatic, semi crystalline polymers, exhibit superior properties than existing polyphthalamide (PPA) materials in terms of mechanical strength and toughness across a broad range of temperatures. Grades are available with glass fiber reinforcement ranging from 30 to 50%.

“ForTii MX grades will become essential solutions for metal replacement,” says Ralf Ponicki, Program Manager for die cast replacement. “In terms of heat deflection temperature (HDT/A 305°C) and toughness, they are considerably better than most other PPAs currently on the market. Injection moldings in ForTii MX will be able to compete advantageously with parts die-cast in aluminum, magnesium and zinc.”

Injection molding with high performance thermoplastics already provides a cost reduction over metal die-casting of typically 20 to 30%, but use of ForTii MX allows cost savings up to 50%. The potential for improvements in weight savings is on a similar level. Moreover ForTii MX provides extra possibilities for functional integration, product safety improvements, and simplification of logistics and handling efforts.

“ForTii MX exhibits a comprehensive property profile that some competitive solutions can only partially cover with using additional blend technology,” says Ponicki. “Many pure PPA based compounds retain their good mechanical strength and dimensional stability up to around 100°C but in environments with temperatures above 130°C the mechanical strength drops severely. This effect is compensated for sometimes by using blend technology, but this sacrifices dimensional stability as well as mechanical strength up to 100°C. ForTii MX (PPA) reportedly combines the best of two worlds - best mechanical performance (especially impact strength) in combination with high dimensional stability at ambient elevated (100°C) and high temperatures with limited influence of moisture.”

DSM is continuing to develop new series of ForTii aimed at die-cast metal replacement. “We still have at least one ace up our sleeve,” says Ponicki. The company plans further announcements later this year.