Taming extreme forces

Extreme may be the new buzzword for dangerous sports and high-caffeine sports drinks, but for vehicle design engineers extreme has always been part of the job.

"The challenge is to keep critical joints fail-safe not only under expected use, but also under extreme use," said Frank Metelues, a design engineer at Dana Corporation, a supplier of axle, driveshaft, engine, frame, chassis, and transmission technologies to vehicle OEMs with $9.1 billion in worldwide sales last year.

"You've got to do this while hitting all the required pricepoints for performance, manufacturing, and warranty, and some drivers are always going to push the limits," continues Metelues, who works in Dana Corporation's Traction Technologies Group.

"Uphill towing or off-roading just compounds the extreme loading, vibration, and thermal forces engineers contend with."

While engineers are tasked to design vehicle components that reliably withstand extremes of use - from shock, torsional, axial, and vibrational loading to thermal resistance and lifecycles of use - they must always keep their eyes on the bottom line as well. That means issues such as the cost of performance, assembly, maintenance, and warranty must also be optimised. But until now, engineers have faced significant drawbacks using traditional fastening methods.