Why are automakers not embracing stainless steel in structural applications to reduce overall weight and create safer and more fuel-efficient vehicles?
Usually when you think of stainless steel in cars, the exhaust system, the trim or the DeLorean DMC-12 from the “Back to the Future” movies come to mind.The unpainted stainless body panels of the DeLorean made for a unique looking sports car/time machine, sure, but that seems to have done nothing for the mainstreaming of stainless steel use in the manufacture of passenger cars.
LIGHTER BUT STRONGER
The current focus in automobile design is fuel efficiency. The body panels of a DMC-12 were certainly heavier than similar ones made of aluminium or steel in today’s lightweight cars and trucks, sure, but that doesn’t mean stronger and more corrosion-resistant, per-ounce structural stainless can’t be used in pillars and other applications where bigger doesn’t always mean better or safer.
FUEL EFFICIENCY WITH STRENGTH
Fuel efficiency is improved when the weight of the vehicle is reduced. The “lightweighting” trend has been focused on the use of more aluminium in design; however, perhaps it’s time to re-examine stainless in structural automotive applications.
We may never see another DeLorean-like car with stainless exterior panels, but that doesn’t mean there’s no place for stainless in automobile production.
Five years have passed since a European consortium of stainless steel producers, automobile OEMs and other industrial partners concluded its “Next Generation Vehicle” project.
The aim of this 5-year project, begun in 2004, was to examine areas in which stainless steel could be used in the design and manufacture of passenger cars.
HOW TO STRENGTHEN A LIGHTER VEHICLE
The study reported that certain stainless steels could replace carbon steel in key structural areas while still reducing overall weight. Significant advances were made in establishing guidelines for the proper use of stainless steel as a prerequisite. A cost model was developed which allowed for a direct comparison of different materials and different production methods through all stages of production. Software programs were developed to simulate forming and crash behaviours which were then verified by designing, building and crashing different types of B-pillars, the structural members in a car where the driver and passenger side windows end.
The Next Generation Vehicle deliverables and database established a sound basis for the use of stainless steels in automotive series production, particularly for B-pillars.
SO, WHAT HAPPENED?
Unfortunately, the European project seems to have fizzled out with the economic crisis. Now that the economy has improved and stainless alloy surcharges are at a low point, why aren’t stainless mills working to promote stainless steel in automotive structural applications.