BMW today announced it has taken a 15.16 percent stake in SGL Carbon SE, a leading manufacturer of carbon fiber and carbon fiber reinforced plastic (CFRP). This move should surprise no one, as BMW has been closely partnered with SGL for several years now, but it does put a point on the near future of mass-produced vehicles with carbon fiber or CFRP components.

The value of carbon fiber is obvious: it's light, it's strong, and, for luxury and performance enthusiasts, it carries a certain cachet of exclusivity. That last factor may be changing as wider use is made, but it's still attractive in its own right, and its lightweight structural virtues are nearly inimitable.

As BMW's Friedrich Eichiner put it, "Lightweight construction will play an increasingly important role in the automobile industry in the future. Our stake-holding in the SGL Group is a logical step…"

BMW Megacity Vehicle official photos

BMW Megacity Vehicle official photos

This, of course, isn't the first tie-up between BMW and SGL. The two companies already operate a joint venture, owned 51 percent by BMW, for the construction and operation of a carbon fiber plant in Moses Lake, Washington. The plant is making CFRP that facilities in Germany then turn into components for future vehicles and concepts, including the body and other pieces of the i3 and i8.

Mercedes-Benz has made its own partnership in the carbon fiber field, with leading Japanese manufacturer Toray. That partnership is expected to yield CFRP and carbon fiber parts for more conventional vehicles than BMW's i range. The 2013 Mercedes-Benz SL-Class is expected to be the first to benefit from the Toray deal.

Audi, likewise, has teamed up with Germany's Voith to source its carbon fiber materials and components. Unlike BMW and Mercedes, however, Audi's plans for its expanded carbon fiber use haven't been as explicitly disclosed.

Even as carbon fiber rises in popularity and availability, however, manufacturers aren't leaving aluminum and steel for dead. Quite the opposite, with all three leading German luxury carmakers, plus most mainstream carmakers employing new alloys in every-increasing variety within a single vehicle to suit structural, NVH, and impact needs.

Ferrari, for instance, recently said it will be sticking with aluminum even as rivals like Lamborghini and upstart McLaren Automotive delve heavily into carbon fiber with the Aventador and MP4-12C. Production cost, complexity, and speed of construction all work in aluminum's favor, and Ferrari thinks it can still achieve its weight, rigidity, and performance goals with the lightweight metal. With many alloys for many purposes, plus a wider variety of construction methods including welding and epoxy bonding, aluminum does offer greater flexibility--for the present.

2013 Mercedes-Benz SL-Class technology preview live images

2013 Mercedes-Benz SL-Class technology preview live images

Mercedes-Benz's upcoming 2013 SL-Class is another example, employing stamped, extruded, and cast aluminum in addition to steel, which will be used in addition to CFRP components. Audi's next-generation R8, due in 2014, will go one step further, using a hybrid aluminum/carbon fiber structure that's said to weigh at least 45 pounds less than the current car's all-aluminum chassis.

For larger vehicles, aluminum continues to make even more sense. Audi's upcoming 2013 Q7 will shed as much as 650 pounds compared to the current model through more extensive use of aluminum in the body and chassis. Volkswagen and Porsche have already done nearly as much with the Cayenne and Touareg, which share a platform, cutting 400 pounds from their SUVs. The slightly larger Q7, which will also share the same underpinnings, can save even more weight due to its size.

Saving that much weight in a large SUV with carbon fiber at today's prices would be prohibitively expensive, however, even with the established partnerships between Volkswagen Group companies and carbon fiber makers.

As these joint ventures and partially-owned partnerships with carbon manufacturers continue, however, prices will fall, and use will become more widespread, helping carmakers reach ever-tightening fuel economy and emissions targets while--hopefully--preserving or improving vehicle dynamics even as engines in many cars downsize displacement in favor of forced induction, hybrid drive systems, and fully electric powertrains.