Structural core materials are used to provide sandwich composites with high bending stiffness and overall low density. Due to these physical properties, core materials are primarily used in aerospace and wind energy equipment to improve the strength of materials and reduce their weight. Moreover, the need for superior performance materials and environment-friendly products in a wide range of industries and emerging economies has led to increased demand for core materials. Sweden-based Diab, a company that has remained at the leading edge of composite core material development, is efficiently working toward fulfilling this need. The company offers a complete range of high-performance core materials, numerous finishing options, and kit solutions, as well as engineering services and technical expertise to multiple industries, including marine, wind energy, transport, and aerospace.

“With over 30 years of experience as a supplier to the aerospace industry, Diab has the products and experience to optimise life cycle cost and decrease environmental impact,” says Aurelién Lafforgue, market segment manager aerospace, Diab. For aerospace applications, which require lightweight and durable structures, Diab offers high-performance core sandwich composite solutions with the highest strength per weight ratio for all aerospace applications. These properties allow for reduced fuel consumption while simultaneously increasing range and payload. Composite structures allow for greater impact resistance, thus providing more safety and protection against erosion and, at the same time, retain their strength, reducing the need for inspection, maintenance, and repair.

Diab’s wide range of core materials for use in sandwich composites possesses specific characteristics suitable for various conditions. For instance, the company developed Divinycell F, a polyethersulfone (PESU), recyclable foamed core material in 2009. Divinycell F is a superior alternative to traditional honeycomb core materials and is ideal for aerospace applications particularity in aircraft interiors, seating, lining and monument. It features excellent fire, smoke, and toxicity (FST) properties, mechanical properties, and processing characteristics. In addition, Diab’s Divinycell F meets the global regulatory requirements for commercial aircraft interiors and is one of the few core materials that offer exceptional OSU heat release performance and nearly zero smoke, which is well within industry requirements. The core material is compatible with common aerospace composite manufacturing processes and performs well in crush core press moulding as well as traditional vacuum bag moulding.

Illustrating the usage of Divinycell F for interior aircraft applications, Aurélien Lafforgue mentions how Safran Seats, a leading aircraft passenger and crew seat manufacturer, decided to leverage Diab’s core materials over honeycomb materials. The client selected Divinycell F based on its inherent cost benefits and durability. And with unique forming capabilities, Divinycell F enabled the manufacturer to complete part fabrication in fewer steps, saving labour costs and time. In addition, Divinycell F allowed for more innovative and complex designs while maintaining toughness. Another core material, Divinycell HT developed by Diab was used by Cirrus Aircraft, a piston engine aircraft manufacturer to build an all-composite airframe and sandwich construction on its jets, the SR22 and the newest Vision Jet.

Diab caters to every facet of the composite design and manufacturing process. The company delivers ready-made engineered kits—pre-cut parts that are shaped as necessary—to substantially increase efficiency, save costs, and improve quality. This helps minimise raw material usage and manufacturing waste. With high-performance solutions and cutting-edge engineering services, Diab is positioned to serve customers locally while offering the benefits of a local company. With a dedicated R&D team, Diab is continually expanding its portfolio of core materials and services. The company is also working to reinforce its position as a worldwide leader in composite core materials. “We honour our commitment to customers by focusing on what is required to make their products stronger, lighter, and smarter,” states Aurélien Lafforgue.