Composites – A neophyte’s quandary
This month’s column comes on the heels of my return from Europe, where I visited JEC World in Paris and made visits elsewhere. Once again, I saw continued progress toward a more ubiquitous future for composites, and I made some general observations about what some of that future might look like. But that and a meeting I had along the way led me to ponder a hurdle we still need to conquer, one that has wide-reaching implications. First, the things that stood out to me:
There could be a place for composites in e-mobility. Frankly, I’ve had some doubts about what role composites might play in the world of electric, and especially, autonomous electric vehicles. With the cost of batteries dropping at a rapid pace, how much will vehicle mass matter, especially for ride-sharing/local routes where range is less of an issue? Will a metallic spaceframe with “snap on,” low-modulus neat plastic body panels achieve the styling objectives of driverless vehicles? There don’t seem to be clear answers. Nonetheless, I saw several examples in Paris, albeit prototypes, of integrated structural battery boxes doubling as skateboard-like chassis elements. The battery enclosure, if nothing else, appears to be a logical composites application.
Automation is making a difference. Last year, numerous manufacturers were showing off machines that could automate layup and downstream processing. This year, Voith Composites (München, Germany) showed a fully automated layup, infusion, trim and assembly cell for the Audi A8’s carbon fiber back panel and package shelf that is in production. This didn’t happen overnight — Voith and Audi announced their partnership back in 2011 — such transformative technologies take time to mature.
Hybrid structures are gaining traction. Although most are still patches of continuous fiber thermoplastics (UD tape or woven organosheet) overmolded with short fiber thermoplastics of the same polymer family, the most highly structural examples I saw were thermoset — continuous carbon fiber prepreg inserts overmolded with high-load carbon fiber sheet molding compound (SMC). Clearly, these hybrid technologies help address waste and cost. The challenge here is designing and modeling the structural performance because no one single code has been developed yet to address this mix of materials, either in thermoplastic or thermoset.
It was as I observed and interpreted technological possibilities that I met with a major industry supplier, who offered up this provocative question: “If you showed up at this event without any understanding of composites, how would you find your way around?”
That still has me thinking. Most who attend JEC have a grasp of polymer composite basics and many have considerable experience or expertise in one or more composites applications. We come looking for, and can recognize, the new and novel and can discern the impact it might have. If you’re a new hire at an aerospace or automotive firm, chances are there are those who have preceded you who have at least a basic understanding of composites and can point you in a few directions. But say you’re a civil engineer, trained in concrete bridge construction, and your boss sends you to the world’s largest composites exhibition to learn about this new technology called “composites” he’s been reading about? Or you work for a utility company where local infrastructure has been ravaged by a hurricane and have heard that composites can help “harden the grid,” but you only know wooden poles and metallic transmission towers? Or you now make a product from wood, metal or plastic, but you’re “looking into” FRP? What then?
An oft-cited concern is that new engineers are not exposed to composites as part of their materials science courses. Another is that the public at large has little understanding — or appreciation — of the ways composites can make products more functional, stylish and longer lasting. No simple solutions there. But for trade shows? How about this: When you visit an art gallery or major museum, you are often greeted by a docent, typically a volunteer, who is well versed in the items on display and who offers to help you appreciate their significance, putting into context the exceptional creations or findings among the treasures there. Perhaps JEC, CAMX and other large composites trade shows should consider hanging a large sign at the entrance that says “New to composites? Start here,” with an arrow pointing to an information desk staffed with “old hands” that have been around the industry a while. I know that I, and many others, would be glad to mentor such neophytes for an hour or so as they start their discovery of the composites universe. Chances are, we will learn something as well.
Tried-and-true materials thrive, but new approaches and new forms designed to process faster are entering the marketplace.
The structural properties of composite materials are derived primarily from the fiber reinforcement. Fiber types, their manufacture, their uses and the end-market applications in which they find most use are described.
Yes, advanced forms are in development, but has the technology progressed enough to make the business case?