Vehicle weight has increased at a rate of 1.2% annually over three decades.  Today the average light-duty vehicle pushes the scales at a hefty 3,814 lb (1,730 kg).  A weight reduction of 10% translates into an outstanding 7-8% fuel savings.  Understandably, automakers proactively look for ways to reduce weight, in an effort to improve fuel efficiency, and enhance consumer appeal of their line-up.

Automakers use a variety of methods to reduce the weight in their vehicles, most notably substituting components with lighter weight materials.  While this is a very sound strategy, automakers must balance weight, performance and cost.  Any material substitution has the potential to yield benefits or conversely, create problems.  Examples: switching from steel to carbon fiber could yield weight reductions, but increase costs significantly; switching a component from steel to magnesium could decrease weight but decrease performance.  In general, the amount of weight reduction obtained by replacing steel is greatest when replaced by polymer composites, followed by magnesium and aluminum.  Recyclable aluminum has proven to be a sound alternative in terms of cost, corrosion resistance, yield and strength.

Die-cast parts represent roughly 80% of aluminum in vehicles.  The average vehicle has two to six die-cast electronic module assemblies.  The metal case is needed to protect components and dissipate heat being generated by power components.  A stamped aluminum case is about 50% lighter and uses significantly less aluminum than a similar die-cast aluminum case design.  The bigger the case, the bigger the savings.

The scale is not the only measure of success.  Die-cast and stamped aluminum case test results show minimal differences in thermal performance.  In addition, stamped cases demonstrate excellent resistance –better than die-cast—to environmental corrosion from abrasive salt spray, one of the most corrosive substances encountered on the road.

Stamped aluminum cases also provide a cleaner, faster process, and greater design flexibility for automakers.  Unlike process-heavy and maintenance-intensive die-casting, which requires mold replacement, stamping dies can produce millions of parts without the need for replacement.  Potential applications for stamped aluminum alloy include all automotive electronic control modules, including ECM shielded and filtered applications on-engine, underhood, and in the passenger compartment.

An automaker replacing die-cast aluminum with stamped aluminum cases can reduce weight (up to 50% or more), cost (30% savings or more), and improve manufacturing efficiencies and environmental performance.  Contact Molex to jumpstart weight loss goals with a stamped aluminum assembly solution.