High-Performance Composites

MAR 2013

High-Performance Composites is read by qualified composites industry professionals in the fields of continuous carbon fiber and other high-performance composites as well as the associated end-markets of aerospace, military, and automotive.

Issue link: https://hpc.epubxp.com/i/110847

Contents of this Issue


Page 41 of 67

update: automotive Composites machined steel and nickel shell). To help ensure a good molded finish on the part backside, the press is fitted with intensification tools. These provide a better B-side aesthetic on panels such as fenders that are not bonded to an inner panel, and they ensure a consistent surface and gap between bonded panels, such as roofs and hoods. Previously, these lower-cost, rigid structures (a/k/a caul plates) were manually inserted between the laminate and vacuum bag, which is one big reason why the old process took 60 minutes. To keep heating/cooling systems simple and tooling costs down, the press and materials that go into it have been designedfor processing at a constant molding temperature (200°C/392°F) — more like thermoplastics than typical thermosets — and relatively low pressures. "The preform can be hot loaded and demolded without post-cure," Starkey says. "A fast 10-minute cycle time is achievable." Unlike resin transfer molding (RTM), the new system doesn't need complex injection equipment to get resin into the tool; and the more drapable semipreg makes complex geometries easier to fill with fewer dry spots. Although he says they're still working out the upper and lower threshold of process parameters, Starkey adds that the system's low forming pressures give his team a lot of freedom regarding tool substrate selection and this, in turn, has led to "a lot of novel ideas besides how to physically form the parts." "We wanted to be able to maintain the same level of material performance our SPRINT CBS product is known for while reducing cost and labor content, and increasing our manufacturing capacity," Starkey sums up. "We've stripped away a lot of manual processing," he emphasizes, noting that the optimized material format reduces the degree of preforming needed to mold complex features "and delivered a net-shape part without a lot of trimming. This gives us cycle-time advantages and, therefore, access to larger-volume platforms." Assuming a 10-minute cycle, the process should produce as many as 40,000 parts per year per tool set, a rate roughly an order of magnitude faster than current thermoset CFRP processes. Starkey's team developed the process on an in-house prototype press and small test-plaque tool and then took it out to the field and trialed it at a large OEM and a large-tier supplier using a full-size press and production tools. The results have been very promising. Starkey acknowledges that the costs and production speeds of CFRP panels are still impractical for conventional midsized and economy cars, but he feels the supersport and premium sectors are viable targets for the first application of the new laminate/process combination. "The commercial question is, Will the volume [of a platform] demand this process?" Starkey notes, but adds. "All the pieces are there and this technology is ready for a commercial launch." Learn More @ www.compositesworld.com Read this article online | http://short. compositesworld.com/WTJigQb9. Read more about the CBS process in "Gurit CBS for the Aston Martin DBS," in HPC's sister magazine Composites Technology (CT February 2010, p. 24) or visit http://short. compositesworld.com/DvXgteYR. Precision Tooling and CNC Machining for the Composites Industry Precision Steel Invar NVD Nickel Weber Manufacturing Technologies Inc Tel 705.526.7896 • Midland, ON www.webermfg.ca 40 | high-performance composites

Articles in this issue

Links on this page

Archives of this issue

view archives of High-Performance Composites - MAR 2013