Automotive composites: A bit of deja vu?
CT columnist Dale Brosius, a consultant and the president of Dayton, Ohio-based Quickstep Composites, recalls predictions made back in the 1980s about autocomposites — predictions that are yet to be fulfilled.
Recently, I was cleaning my office and came upon a few items from several decades ago. The first was a group of pictures of a composite front-end structure (see photo) on a Ford Escort, produced via resin transfer molding (RTM). It featured fiberglass and vinyl ester resin, the latter supplied by my employer at the time, The Dow Chemical Co. (Midland, Mich.). The vehicle was on exhibit in January 1986, in the Dow booth at the SPI Reinforced Plastics and Composites conference, held in Atlanta, Ga.
The front-end structure had the basic configuration of its steel production counterpart. Foam core filled the hollow spaces of the welded steel structure in the upper and lower rails. The structure began at the door hinge pillar, with extensions up the A-pillar and along the rocker panel, and extended forward to the radiator support. Each molded side integrated 44 steel stampings (demonstrating exceptional part integration) and weighed 33 percent less than the welded steel part. The vehicle passed all NVH (noise, vibration and harshness) testing, and came close to matching steel in frontal crash testing … but never made it to production.
I also came across two 50-plus-page reports I authored at the ends, respectively, of 1985 and 1986, on the state of automotive composites development among the Detroit “Big Three.” One passage from the December 1985 report is especially interesting:
“What process will be used to fabricate the all-composite vehicle? Best guesses indicate it will be something of a closed mold, resin injection process, like high-speed resin transfer molding (RTM) or resin injection molding (RIM). The necessary core materials and required fibers will be placed into the mold by use of preform technology. A high degree of automation will be in place to ensure consistency. At this time, it is not known what cycle time will be required, but less than five minutes is not an unreasonable target.”
That prediction could have been written two or three years ago. The fact that it was written almost 30 years ago shows how difficult it has been to make significant penetration into the primary structure of mass-produced vehicles. Back in 1985, carbon fiber was not considered an option, so all the work was done in fiberglass. High-pressure RTM, with carbon reinforcement, is only now becoming the process of choice for structural parts — at least at BMW — and cycle times are, indeed, approaching the five-minute mark. But for truly large-volume platforms, we need to reach two to three minutes, so there’s still a lot of work to be done.
I took the picture of the front-end structure with a Canon SLR film camera — many years before digital cameras became mainstream. And those reports? I hand wrote every word and table and handed it to an office secretary (yes, that was the term used then) who typed it into an IBM PC running WordPerfect software. The reports were stored on 8-inch (200-mm) “floppy” discs, and neither report included graphics (a feature not then supported by the software).
In 1986, cell phones were fixed inside vehicles or, if mobile, were the size of a briefcase. The fax machine was the fastest mode of transmitting data, and we projected images during presentations that were carried on black-and-white transparency sheets, produced on a copier — no laptop or tablet computers, no color laser printers, and no World Wide Web (Netscape was still eight years away). Today, we can videoconference from our pocket-sized mobile phones, produce and send videos and large documents around the world at the speed of light. And how many of us still have a “secretary” or “personal assistant” to create presentations? It is truly amazing how innovative the IT world has been — and continues to be.
By comparison, automotive innovation is exceptionally slow. Beyond the part described above, I was involved during the 1980s in the development of composite leaf springs, driveshafts, crossmembers, truck boxes, engine components and full underbody structures. It seemed a “golden age” of composites experimentation. Some of these made it into (and then out of) production in the subsequent two decades, but the all-composite body-in-white failed to materialize. There is a lot of activity in this space these days, but as the saying goes, “I’ve seen this movie before.” Will this time be different? I sure hope so.
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