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J U L Y 2 0 1 4 | 9 COMPOSITES: PERSPECTIVES & PROVOCATIONS COMPOSITES: PERSPECTIVES & PROVOCATIONS Dale Brosius is head of his own consulting com- pany and the president of Day- ton, Ohio-based Quickstep Com- posites, the U.S. s u b s i d i a r y o f A u s t r a l i a - b a s e d Quickstep Tech- nologies (Bankstown Airport, New South Wales). His career includes a number of positions at Dow Chemical, Fiberite and Cytec, and for three years he served as the general chair of SPE's annual Automo- tive Composites Conference and Exhibition (ACCE). Brosius has a BS in chemical engi- neering from Texas A&M; University and an MBA. Since 2000, he has been a contribut- ing writer for Composites Technology and High-Performance Composites. A AEROSPACE & INDUSTRIAL NEX T-GEN ADVANCED COMPOSITES: A T WO-WAY STREET? utoclave processing of prepregs in the aerospace market is held up as the "gold standard" in terms of what is possible, because this method achieves mechanical performance at the lightest weight. "Aerospace quality" is often used to describe any advanced composites that meet this standard, regardless of the method or material used. Molders in in- dustrial markets could beneft from such strength, stiffness and mass savings, but for the most part, they have historically had to settle for less — lower properties and fber-volume fractions, and higher void contents — to hit the lower cost tar- gets necessary to make such applications viable. But, going forward, that gap is like- ly to shrink considerably, creating a new dynamic between the two sectors. There's no question that the aerospace and defense sectors spurred most of the advances in carbon fber and carbon f- ber composites during the past 40 years. Initially funded by Cold War defense budgets, the signifcant advances that made PAN-based carbon fbers stronger and stiffer were complemented by suc- cessive generations of epoxy resins with increased toughness and other thermo- sets that perform at higher temperatures. Extensive material qualifcation data- bases were developed, and fabrication techniques were enhanced to squeeze out as much performance as possible. But these upgrades came at increasingly greater cost — affordable for builders of jet fghters and commercial aircraft, but beyond the reach of those who make, for example, automobiles, wind turbines, bridges and offshore oil platforms. Today, all signs point to increasing penetration of carbon fber composites in aerospace, using not only conventional technologies, such as automated tape laying and fber placement and autoclave cure, but also, at some level, out-of-au- toclave (OOA) methods. That penetra- tion will be driven, at least in part, by the need to increase production rates, but we are still talking cycle times of hours. In the automotive sector, two- to fve- minute cycles, with minimal waste, are a must. Prepreg costs of more than $50/ lb ($110/kg) are acceptable in aerospace, where a kilogram of saved weight is worth a $600 premium. Not so in the industrial world, where fber costs need to fall to $7/ lb ($15/kg) or less — ideally under $5/lb ($11/kg) — to make economic sense for mass adoption. Big initiatives are underway to drive costs down and production rates up for industrial-grade carbon fber compos- ites — several in Europe and Japan, and the proposed U.S. Department of Energy (DoE)-funded composites manufacturing institute I discussed in March (visit short. c o m p o s i t e s w o r l d . c o m / U S I n v e s t ) . Certainly, elements rooted in aerospace technology can be "starting points": Com- posites design/simulation software, tech- niques for machining carbon composites and automated prepreg layup come to mind. But the mindset of those attack- ing the core issues must be frmly rooted in the industries they pursue. The sense of urgency is much greater in industrial markets. Time frames for technology de- ployment are two to three years, while 10 years or more is not unusual in aerospace. All of the processes are, technically, OOA, yet the drive will be "autoclave quality" parts in minutes, not hours. Automakers produce metal cars in highly automated assembly plants — this same philosophy must be applied to composites. Industrial fabricators, then, will have to take what has gone before in aerospace and improve and adapt it signifcantly to meet cost and rate requirements. If car- bon composites are to enter the main- stream in these markets with strong pen- etration, low-cost fber won't be enough. New materials and processes must be devel- oped, characterized and commercialized. As these next-generation develop- ments are realized, industrial markets won't be the only benefciaries. It'll be a two-way street. The aerospace industry stands to beneft greatly from industrial investment in carbon fber composites, not unlike it did decades ago from high- speed metals processing. To meet au- tomotive and wind turbine production rates, prepreg tape and tow placement speeds must be greatly improved, espe- cially for complex geometries, and com- bined with rapid stamping of thermoplas- tics or fast-curing thermosets. Automated gantry machines will be developed for draping continuous fabrics in wind blade tools. High speed, wide-area nondestruc- tive evaluation must be implemented. Simulation models for designing com- posite and multimaterial structures and for predicting manufacturing variability and part performance in various load- ing conditions must mature. Every one of these innovations could make compos- ites-intensive aircraft production easier and less expensive. To date, most advanced composites technology has come from aerospace. But 10 years hence, many advancements could be fowing in the opposite direc- tion. If so, we may well be able to say the "age of composites" has arrived! 0714HPC Perspect&Provocat-OK.indd; 9 6/17/2014 10:10:00 AM