CompositesWorld
Issue link: https://cw.epubxp.com/i/697353
CompositesWorld.com 17 TRENDS Now ready to be 3-D printed: Composite tooling The polymer additive manufacturing research team in the Department of Energy's Manufacturing Demonstration Facility (MDF) at Oak Ridge National Laboratory (ORNL, Oak Ridge, TN, US) reports that it has successfully fabricated autoclave- capable carbon fber composite molds, using the Big Area Additive Manufacturing (BAAM) machine, a large-scale 3-D printer developed in collaboration with Cincinnati Inc. (Cincinnati, OH, US). Working in collaboration with numerous industry partners and materials suppliers, ORNL developed the molds from two carbon fber-reinforced, high-temperature thermoplastic materials. The frst material combination features polyphen- ylene sulfde (PPS) reinforced with a high loading of carbon fber supplied by TechmerES (Clinton, TN, US). The second combination features a polyphenylsulfone (PPSU) from BASF (Wyandotte, MI, US) that is compounded by Techmer with reduced carbon fber loading. Both fber/polymer combina- tions have been tested and proven in the autoclave process. The team fabricated nine concave-shaped molds in total, each measuring about 1m by 0.8m (see photo). Each tool was either machined and uncoated or coated and not machined, in order to assess its vacuum-holding capability. Subsequently, the autoclaved molds, trialed at The Boeing Co.'s (Chicago, IL, US) St. Louis facility (MO, US), withstood two cycles at 121°C and 30 psi (2.07 bar), followed by a second cycle at 177°C and 90 psi (6.21 bar). Each cycle was 2-3 hours long. Dr. Ahmed Hassen, postdoctoral researcher at ORNL, and Dr. Vlastamil Kunc, ORNL's polymer materials team lead, say that the autoclave trials provided promising results, with only 0.002-0.004 inch (0.05 mm-0.10 mm) maximum deformation after two cycles. How many autoclave cycles these 3-D printed tools might tolerate will be determined in future testing. The benefts of such molds are obvious in terms of time, material and cost savings. "Companies can save a lot of time by printing molds in-house," Hassen contends. "They no longer need to wait for months to get their parts made." It is expected that autoclave-capable materials for large- scale 3D printing will be commercially available late this year. Read more about BAAM | short.compositesworldcom/3DPrintCar Source | ORNL