1st PEEK thermoplastic structural component in the A350.

Airbus Helicopters is replacing aluminum in a machined fitting in the aircraft passenger door of the Airbus A350-900 with a high-modulus, carbon fiber-reinforced high performance polymer.

The brackets, now manufactured from Victrex PEEK 90HMF40 has been developed by Airbus Helicopters in Donauwörth and is in serial production at Dutch Thermoplastic Components for commercial use after receiving the relevant component qualification.

Source: Victrex

The successful substitution of this metallic fitting has resulted in a 40% reduction in weight and costs.

The injection-molded polymer solution replaces the higher cost manufacture of the bracket machined from an aluminum block.

The fiber-reinforced polymer (FRP) structure of the A350 XWB’s aircraft door uses an outer skin coupled with a bracing structure on the inside.

This PEEK thermoplastic fitting connects the outer skin to points on the internal bracing structure.

The 2 components form a box-type support structure to exploit the maximum geometrical moment of inertia.

Optimized carbon fiber reinforced plastic (CFRP) drills improves the quality of the holes compared with the previous solution.

“This first application in the A350 is certain to be quickly followed by others”, explained Uwe Marburger, Aerospace Business Development Manager at UK-based Victrex.

The PEEK 90HMF40 is a high-performance polymer with high-modulus fibers (HMF). High strength components can be manufactured from this free flowing, easily processed material.

Its properties cannot be matched by those of the standard grades. For example, 90HMF40 has up to 100 times longer fatigue life and up to 20% greater specific strength and stiffness than aluminum 7075-T6 under the same conditions.

Based on the article “Primary structural component of A350 cabin doors are made with PEEK polymer” published in JEC Composites.