JEC COMPOSITES MAGAZINE - Issue #39 - March/April 2008 - 103

combination of pressure and heat to consolidate the layers and initiate the resin curing reaction, which, in the early days, usually meant resorting to high-temperature autoclave processing. While the use of an autoclave remained the ultimate route to high-performance components, it was seen as a barrier to the wider adoption and application of high-performance composite materials and prepregs in many industries. Simplified processing and a degree of toughness were required to make LTM prepregs more attractive to a wider market. This was achieved, but the reactive nature of the LTM systems still meant a relatively short working life, which delayed the wider acceptance of these materials. However, they experienced considerable success with one-off projects such as SpaceShipOne and GlobalFlyer. ACG has always produced a range of “standard” 120°C curing prepregs. Again, these materials are generally aimed at autoclave processing, but many were capable of low pressure, vacuum-only processing, offering more realistic work lives, albeit not possessing the original lowtemperature curing capabilities of LTM systems. ZPREG® rapid laminating system, in particular, the associated Body Panel System (BPS). The qualities and features of this product finally addressed the issues of achieving high-quality surface finish without high-pressure processing. The VTM range has now grown into a family of structural, tooling, and surfacing systems that offer high performance and excellent surface quality products via lowcost processing routes. While being firmly established in the marine industry, the VTM system has also proved to be a worthy and valuable entry level product for many component manufacturers. Many builders go on to install autoclaves and use other higher-temperature cure systems. GlobalFlyer – Courtesy of Virgin Atlantic GlobalFlyer Recent applications One of the most recent applications of ZPREG® is on the Farbio GTS super car, which has a space-frame chassis completely clad in the BPS240 carbon fibre body panel system (ACG’s ZPREG® rapid deposition system). With its integrated surface film, BPS240 is a stable, high-temperature system that is capable of producing and maintaining in-service Class A surfaces. The system offers enhanced moulding capabilities, excellent and stable surface quality, effective processing benefits and a significant cost saving over traditional prepreg technologies. When compared to traditional advanced composite materials, BPS240 panels can be moulded from highquality, low-cost composite tooling, thereby reducing manufacturing times by as much as 50%. Courtesy of Farbio Sports Cars/Flow Images Fully-controlled technologies ACG’s VTM® (Variable Temperature Moulding) system is derived from both the LTM and MTM cure chemistries and offers optimised low temperature, low-pressure processing, and flexible cure temperatures between a modest 65°C and 120°C, with “step ahead” cure. Moreover, autoclave curing is no longer needed, while the extended working life of one month provides a wider window of operation in which to complete the laminating process. Resin rheology is controlled to optimise fibre wet-out, but not at the expense of excessive resin bleed. As stated earlier, the autoclave is the ultimate route to general laminate and surface quality. Low-pressure prepreg processing has always suffered from poor surface quality and a high level of subsequent surface re-work. A parallel development of the VTM system, which originally targeted the automotive industry, has also been embraced by the marine and exclusive sports car industries. The development in question is the Farbio GTS Many of the lessons learnt from past experience are now being integrated into the next generation of out-of-autoclave MTM prepregs and film infusion systems. With simplified processing and further developments in toughening mechanisms, these systems offer the performance levels demanded by the aerospace industry. Products such as MTM®44-1, MTM®45-1, MTM®46 and MVR444 form ACG’s new generation of out-of-autoclave processing systems currently in use or under qualification for a variety of civil and military applications. With the recent launch of Virgin Galactic, which is the Virgin Group’s new commercial spaceline, commercial spaceflight will take a further step forward by offering the first commercial sub-orbital passenger space service. Virgin Galactic will operate five spaceship systems manufactured from ACG’s MTM®45-1 prepreg resin system by The Spaceship Company, a joint Venture between Sir Richard Branson’s Virgin Group and Burt Rutan’s Scaled Composites. Taking advantage of the characteristics of the out-of-autoclave processing systems, ACG has now travelled full circle by developing a new series of out-of-autoclave LTM tooling systems that address the evergrowing need for larger tools, especially those required to satisfy the present developments in the commercial aircraft market. Having installed additional state-of-the-art prepreg processing equipment for new Fuselage demonstrator tool production lines at its UK using out-of-autoclave facility, ACG has its sights set technology on its future. These new production lines, which are part of a multimillion pound investment from its parent company, Umeco plc, set the scene for further success in the aerospace market. More information: www.advanced-composites.com No39 March - April 2008 / JEC Composites Magazine

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JEC COMPOSITES MAGAZINE - Issue #39 - March/April 2008

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #39 - March/April 2008