SFS Intec, TxV to redesign aircraft bracket using thermoplastic composites
SFS intec Inc. (Wyomissing, Pa., U.S.) announced March 6 it is partnering with TxV Aero Composites (Bristol, R.I., U.S.) — a joint venture between Victrex plc (Lancashire, U.K.) and Tri-Mack Plastics Manufacturing Corp. (Bristol, R.I., U.S.) — in the re-design of an aircraft storage bin bracket. Originally made from aluminum, the new bracket will be made of VICTREX AE 250 composites overmolded with VICTREX PEEK (polyetheretherketone) polymer. SFS is qualifying TxV’s hybrid overmolded composite part for use in a commercial aircraft. The weight, size, complex geometry and high load-bearing specifications of the overhead storage bin bracket reportedly made the SFS part a suitable candidate for the pioneering hybrid overmolding technique at TxV. Another consideration was the 60-70% scrap produced through several milling steps required for the original aerospace grade aluminum bracket.
Sascha Costabel, head of Innovation at SFS Intec GmbH Aircraft Components says, “Our decision to work with TxV is a strategic one. We are convinced that thermoplastic composite components will play an increasingly larger role in the manufacture of aircraft. It may well be that several different technologies will each have a role in the future of aircraft production. TxV’s hybrid overmolding process, is a good option for components that must withstand high levels of mechanical stress and geometries that require multiple processing steps where conventional machining is used.”
TxV says the processing and performance advantages of PAEK thermoplastic composites, combined with state-of-the-art automated manufacturing, position the company to meet the industry’s cost and weight challenges. Finished composite parts, complete hybrid overmolded components and assemblies are reportedly produced using continuous manufacturing processes with cycle times measured in minutes rather than the hours required by thermoset alternatives. The products are said to deliver weight savings of up to 60% over conventional metallic solutions.
“This project represents an exciting commercial application of our overmolded hybrid part technology,” says Jonathan Sourkes, senior account manager at TxV. “SFS intec recognizes the benefits of our approach to part manufacturing in terms of processing efficiencies and overall system cost savings. Scrap reduction, decreased weight, elimination of secondary processing and lower part count are all benefits of moving from metal to a hybrid overmolded composite solution.”
A unique hybrid molding process
VICTREX AE 250 composites are based on the PAEK (polyaryletherketone) family of high performance polymers and are specifically designed for lower temperature processing. This reportedly enables a unique hybrid molding process that combines the strength of continuously-reinforced thermoplastic composites with the design flexibility and proven performance of VICTREX PEEK (polyetheretherketone) overmolding polymers - in this case, VICTREX PEEK 150CA30.
Commercial aircraft use thousands of brackets and system attachments from the cockpit to the tail of the plane. As a result, these components can account for significant cost and weight. The high-performance PAEK polymer-based components can reportedly be manufactured more efficiently than conventional thermoset alternatives and are said to deliver significant weight savings compared to aluminum, stainless steel and titanium while reportedly offering equivalent or better mechanical properties such as strength, stiffness and fatigue.
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