At this year’s JEC Europe show Hexcel is celebrating its 65th anniversary and continuing to lead with innovations in composite materials.
Visitors to the Hexcel stand at JEC will discover some of the latest developments for Aerospace and Industrial markets – from advanced carbon fibre reinforcements for aircraft primary structures to a new low temperature curing prepreg for wind turbine blades.
Airbus A350 XWB Getting Ready for Take-Off
When the A350 XWB makes its first flight later this year Hexcel will watch with pride, as the sole source supplier for all of the aircraft’s composite primary structural parts. These include entire fuselage panels, keel beam, the entire wing (covers, spars and centre wing box) and empennage – all of which are made with Hexcel’s HexPly® M21E prepreg systems and HexTow® IM carbon fibre.
The A350 XWB is the first Airbus with a structure that is more than 50% composites and Hexcel’s content is over $4 million per aircraft. Airbus has loaned Hexcel an A350 XWB Stringer Run Out Demonstrator panel to display at JEC – a part with skins and stringers both built in HexPly® M21E/IMA slit tape and UD tape.
HiTape® Advanced Reinforcements for Out of Autoclave (OOA) Processed Aircraft Primary Structures
HiTape® combines the benefits of automated processing and the cost-effectiveness of infusion technologies - with the high performance achieved with primary structure prepregs. The UD tape based on HexTow® carbon fibre allows dry preforms to be manufactured in a fully automated lay-up process with deposition rates as high as 50Kg/h – without any material splicing or removal of polythene film.
Parts produced with HiTape® reinforcements and HexFlow® infusion resins can be up to 30mm thick with a 58 to 60% Fibre Volume Content. The mechanical properties are therefore as high as those found in parts made with the latest generation primary structure prepregs.
Customer evaluations have demonstrated that significant cost-savings are achievable with HiTape® and the associated vacuum infusion process. HiTape® has been used to great effect by Aerocomposit for wing prototype components. Spirit AeroSystems has also successfully used HiTape® to form the skin of an engine nacelle outer fan cowl – a part which will be displayed on Hexcel’s stand at JEC. Video footage from Coriolis and M Torres will demonstrate the speed and efficiency of the HiTape® preform lay-up process.
Outstanding Performance in Engine Fan Blades Achieved with NEW HexPly® M91 Prepreg
HexPly® M91 is a new epoxy prepreg developed by Hexcel for airframe primary structures and aircraft engines that meets the ever growing needs of aerospace OEMs to manufacture lighter, faster and more efficient aircraft.
HexPly® M91 is used by CTAL – a Rolls-Royce/GKN Aerospace joint venture – to manufacture DOVE demonstrator fan blades for new generation lightweight turbofan engines. Hexcel supplies HexPly® M91 as slit tape which CTAL uses to lay-up the blade in an automated process that produces a complex aerodynamic shape, with a constantly changing thickness across the blade length. The result is as thin as a titanium fan blade - and lighter.
HexPly® M91 provides outstanding performance, including very high toughness and high residual compression after impact (CAI). It gives improved tensile performance in combination with both Intermediate Modulus (IM) and High Strength (AS) carbon fibres. Good hot-wet properties up to 120°C (250°F) are also obtained.
Good tack life and out-life provide flexibility during processing on the shop floor and low exothermic behaviour allows for simple cure cycles of thick monolithic structures.
PrimeTex® Carbon Fibre Reinforcements for Aerospace Structures
PrimeTex® is Hexcel’s patented technology with fibres spread in both the warp and weft direction to provide a uniform weave and gap-free finish. The PrimeTex® spreading process increases the closure factor by 5-8% compared to conventional weaving processes (depending on the carbon tow and FAW).
PrimeTex® carbon fibre reinforcements are ideal for Aerospace laminates as the gap-free structure reduces porosity and requires less part finishing. Low weight PrimeTex® can lower the mass in a composite structure, resulting in even greater weight savings than with standard composite reinforcements. PrimeTex® gives excellent water tightness when used in honeycomb sandwich structures such as aircraft belly fairings or helicopter structures.
HexTOOL® Machinable Composite Tooling Material Selected by CFAN
CFAN, a leader in the field of composite technologies selected Hexcel’s innovative tooling materials to manufacture its composite fan blades for the GE90 and GEnx engines. CFAN studied various tooling materials during its development of composite tooling to support extensive production requirements. Hexcel understood the requirements and proposed HexTOOL® M61 quasi-isotropic tooling material.
As noted by CFAN, an extensive 22 month evaluation of composite tool technologies began, resulting in CFAN selecting HexTOOL® M61.
“Over multiple cure cycles HexTOOL® materials demonstrated high levels of tool dimensional stability, excellent vacuum integrity and tool durability, using standard CFAN operational practices,” says Tom Lednicky, Sr. Manufacturing Engineer with CFAN.
The capabilities and benefits of HexTOOL® include the ability to meet strict requirements for stability and repeatability of tolerances previously accomplished by machined Invar tools, in addition to the improved thermal performance and reduced weight of carbon tools over metal tools.
CFAN reports that they have more than 80 HexTOOL® tools presently in production use, with more planned and on order. HexTOOL® tools are used for the production of the GE90-94, GE90-115B, GEnx-1B and GEnx-2B fan blades.
HexPly® M79 Low Temperature Cure Prepreg for Wind Turbine Blades
NEW HexPly® M79 prepreg from Hexcel is a potential game-changer in the wind blade industry - offering a real option for those who currently manufacture blades by infusion to move to prepreg technology and benefit from superior mechanical performance.
HexPly® M79 has been developed to respond to the industry requirements for a lower temperature curing prepreg that cures more quickly than products currently on the market. A number of cure cycle options are possible with HexPly® M79 including a very low temperature cure cycle of 8-10 hours at just 70°C or a more rapid cure cycle of just 4-6 hours at 80°C. This is a significant time-saving on established industry prepregs where a typical cure cycle for an 80°C curing resin matrix is 10 hours.
With HexPly® M79 there is also a 60% reduction in the risk of an exothermic reaction than with standard wind energy prepregs - yet the new system is based on standard epoxy chemistry that has more than 20 years of proven performance for wind blades. HexPly® M79 also has a very long out life at room temperature of at least two months, which is unusual for such a low temperature curing product.
Due to the low cure temperature of HexPly® M79 the system is compatible with any liquid epoxy resin used for infusion processing. This means that prepreg and infusion processes can be combined in the same blade, combining the twin advantages of stronger laminates and cost-effective processing.
The ultimate performance for wind blades is achieved when HexPly® M79 is reinforced with carbon fibre to provide exceptionally strong laminates that are lighter than those made with glass fibre. This is an enabling technology for the increasingly larger wind blades that are being manufactured – now approaching 100m in length.
HEXPLY® M77 and HEXMC®
A new development being promoted by Hexcel at JEC is the combination of HexMC® patented technology with Hexcel’s unique rapid curing HexPly® M77 epoxy resin system. Hexcel has developed this high performance carbon fibre compound specifically for compression moulding processes that are compatible with large volume automated production, as used in the automotive industry. Hexcel is working with Plastic Omnium to optimize the technology and a demonstrator part using HexPly® M77 and HexMC® technology will be on show at JEC.
PRIMETEX® VERY LIGHT WEIGHT GAP-FREE FABRICS
As a further development of its highly successful PrimeTex® proprietary spreading process technology, Hexcel is launching the lightest 3K gap–free carbon fabric ever produced: PrimeTex® Very Light Weight 98 g/m². This new range of 3K carbon fabrics breaks through the conventional limits for Fibre Areal Weight and opens the door to the cost-effective use of very light plies in composite lay-ups. PrimeTex® Very Light Weight is also 12% thinner than conventional 1K carbon fabrics, which results in lighter structures making it the perfect candidate for surface plies, sandwich construction, structural parts or any other composite components requiring extreme lightness.
For more information on Hexcel’s products featured at JEC Paris Show 2013, visit www.hexcel.com/news for the latest Composite Trends Newsletter.