What are the Downsides to Composites?
They don’t corrode, but they do undergo a photooxidation process. As a result the composites must be painted. And therein lies another Dreamliner technology story. “We’ve come up with an intermediate barrier coating,” says Miller. “Our customers can strip or change the colors of the paint without having to go all the way down to the composite. That means they don’t have to sand.” Another issue isn’t so much a downside as it is a difference. Composite structures require you to approach thermal and electrical management differently from aluminum, which has intrinsically higher electrical and thermal conductivity. How you move current from shorts, for example, is not something you have to think as much about in an aluminum structure. “We’re a lot smarter about how we attack these issues than we were three years ago,” says Miller. Who owns all of the technology developed for the Dreamliner, considering the huge global supply chain involved? “It depends on who pays for it,” says Miller. “If
