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M A Y 2 0 1 4 | 3 1 Mack reportedly achieved manufacturing cycle times measured in minutes. The snap-cure and carbon fber/ther- moplastics trends made it all the more noteworthy that Paul Mackenzie, VP re- search and technology at U.S. based aerospace carbon fber and prepreg supplier Hexcel (Stamford, Conn.), in- troduced a new high-modulus carbon fber (HexTow HM63), a new epoxy (Hex- Ply M92) and, notably, a new snap-cure prepreg epoxy targeted toward automo- tive applications. Characterized as a re- sponse to thermoplastics' incursions into automotive molding, its new HexPly M77 offers a two-minute cure. (Detailed data are available on p. 72. HPC readers interested in carbon fber-reinforced ther- moplastic automotive apps should see HPC's sister publication Composites Technol- ogy's JEC Europe 2014 coverage in June.) With interest in carbon fber/thermo- plastic applications so high, pre-show rumors of yet another new PAN-based carbon fber manufacturer piqued HPC's interest. The rumors proved untrue, but HPC found that the subject of the ru- mors, UHT Unitech Co. Ltd. (Zhongli, Tai- wan), offers not a new fber but a graphi- tization service for composites fabricators who purchase T700-grade PAN-carbon fber from existing fber manufacturers. Unitech president Ben Wang says the company's business model is to unspool PAN carbon fber (3K to 48K) purchased from other sources, burn off the factory- applied sizing, then graphitize it in Uni- tech's patented 2000°C/3632°F microwave ovens. Afterward, Unitech reapplies fber sizing (Wang says he specializes in siz- ings compatible with thermoplastic resins for sporting goods and industrial appli- cations) and re-spools the product. The result? Wang quips that "no one believes it" but he can deliver the equivalent of T800 or T1000 fber at 15 to 30 percent lower cost, because the microwave tech- nology consumes 30 percent less en- ergy than conventional graphitization ovens, processes fber 50 percent faster, and generates no water or air pollution. Most intriguing, he says test results in- dicate that his UT800 and UT1000 prod- ucts are roughly equivalent to those now on the market. He also emphasized that he's not planning to engage in spinning or carbonization of raw PAN fber and is willing to partner with other carbon fber manufacturers interested in adapting his microwave process. System integration: This third trend defned the proverbial handwriting on the wall: Touch labor is out, automa- Hybrid seating for aircraft interiors A JEC Innovation Award winner, Expliseat's (Raispal, France) Titanium Seat is the frst composite aircraft passenger seat to pass dynamic 16G crash tests, yet it tips the scales at half the weight of its nearest competitor. Serial production automotive CFRP Carbo Tech (Salzburg, Austria) celebrated the opening of its second production facility in Žebrák, Czech Republic, a highly automated HP-RTM plant that can deliver 50,000 carbon fiber/epoxy parts per year, like the passenger "tub" (above) for the Volkswagen LX1. Source: Tencate Source: Volkswagen ONE-SHOT NOSE LANDING GEAR DEMONSTRATOR Coexpair SA (Namur, Belgium) displayed a re-engineered composite nose land- ing gear door representative of that currently used on the Airbus A350 XWB. The part was molded out of the autoclave, using Salt Lake City-based Radius Engi- neering's same-qualifed resin transfer molding (SQRTM) process. The part, fea- turing an integrally stiffened double-curvature, was produced in one-shot, and the process is said to be viable for serial production. The sandwich construction of the original was eliminated to reduce cost — I-, J- and T-section stiffeners reportedly provide greater mechanical performance. The door required no post- mold assembly, secondary bonding or mechanical fasteners, and no stitching of preforms or secondary bonding. One-shot processing was enabled by a complex tool that features 50 inserts. Made from A350 program-qualifed Hexcel Hexply M21 prepreg, the door's process parameters and mechanical performance reportedly match those of the autoclaved part. The door also features molded-in reinforced slots that accept its unique composite hinge brackets (see close-up photo, on left). Coexpair contends that the part demonstrates that complex integrated struc- tures can be developed with acceptable lead time,using the same tough prepreg used in the rest of the fuselage structure (rather than relatively brittle RTM res- ins) — two outcomes not previously demonstrated. 0514HPC JEC EuropeReview-OK.indd 31 4/22/2014 3:03:11 PM