Out-of-Autoclave Offers Opportunities in Aerospace

Industry veteran Bob Lacovara began his COMPOSITES 2013 educational session with a prediction: “We’ve probably seen the last aluminum commercial aircraft ever developed. Composites are primed for growth in this industry.”

Lacovara, CCM, CCT-I, principal at industry consulting firm Convergent Composites and former director of technical services for ACMA, led the session “Why Aerospace Out-of-Autoclave Processing is Good for the General Composites Industry.”

He began by highlighting the Boeing 787 Dreamliner, the world’s first large commercial jetliner with a fuselage made primarily of carbon fiber composite rather than aluminum, making the plane significantly lighter and more durable. Boeing says the Dreamliner is 20 percent more fuel-efficient than comparable models and predicts it will save millions of dollars in maintenance costs because composites don’t corrode.

“There is a major paradigm shift occurring in the design and manufacturing of commercial aircraft,” Lacovara said. “Traditional metal designs, which have been used to construct airliners for years, are developing into composites designs. Our industry is at the leading edge and making its way into flight-critical applications, and there’s a projection for huge future demand of composites in the aircraft industry.”

Most structural components have traditionally been manufactured with autoclave processing, Lacovara said. These issues have resulted:

  • Equipment is capital intensive.
  • Operational costs are high.
  • Energy consumption is high.
  • Pressure vessel size limits component size.
  • There are no means to make in-process adjustments.
  • Cycle time is slow.
  • Capacity might not keep pace with projected composites growth.

“There aren’t enough autoclaves available to accommodate the increase in production rates the aircraft industry is going to require,” Lacovara says. “At the same time, new manufacturing methods are available that can produce aerospace-like properties at lower costs. Those methods present a huge opportunity for the composites industry.”

Lacovara continued by discussing closed molding techniques to produce aerospace-like properties at a cost compatible with commercial composites applications. He said application of these progressive molding methods offers the capability to move FRP into higher level structural applications. “The aerospace composites folks are looking at vacuum-infusion processing, several versions of resin-transfer molding and also vacuum-bagged-only prepreg processing,” he said. “What’s of particular interest to the general composites industry is vacuum infusion and resin-transfer molding. A number of applications that once were constrained to autoclave processing are now opening up to a broader spectrum of composites manufacturing. So rather than being required to have a multimillion-dollar autoclave, more companies in the aerospace industry and elsewhere can manufacture structural components within their economic means.”