TRAVERSE CITY, MI – There is an old joke in manufacturing circles that the perfect automotive material exists just beyond the reach of today’s engineers.

It is easy to fabricate and weld, very lightweight and costs the same as mild steel. Unfortunately, the name of the material is a punchline: “unobtainium.”

However, Mike Regiec, manufacturing chief and technical fellow-Body Manufacturing Engineering at General Motors, says new manufacturing strategies and processes actually could make “unobtainium” a reality in the next few years.

A mixed-materials policy GM and other auto makers are pursuing could work magic by creating manufacturing processes that can adapt to the idiosyncrasies of advanced materials, he says.

Materials strategies once were jealously guarded by various constituencies within auto makers that had experience with certain methods or processes. But traditional barriers to new materials, such as specific, established manufacturing processes, are being broken down, Regiec tells attendees at the Management Briefing Seminars here.

“Conventional processes are not allowed to limit choices,” Regiec says, citing a long list of disparate manufacturing methods that would not usually coexist on the same factory floor in previous times, such as spot welding, gas-metal arc brazing, laser brazing, riveting and bonding.

The introduction of a growing number of aluminum and carbon-fiber parts is driving this trend, with both materials requiring special processes and handling for welding, bonding, fabricating, shipping and more.

But GM is learning how to adapt its production processes to more mixed materials, which is controlling cost and production consistency while leading to lighter, stiffer and safer vehicles, such as the new Cadillac ATS and ’14 Chevrolet Corvette.

As new materials are developed and GM’s manufacturing strategies continue to evolve, “unobtainium may be just a few years away,” Regiec says. And this time it doesn’t sound like a joke.