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Thus a new term called “lightweighting” has crept into the automotive lexicon. A recent Ward’s/DuPont survey indicates 60% of respondents view lightweighting, as the “core” to meeting the new standards with all vehicle systems “ranked relatively equally.”
Automakers are attacking the challenge along a broad front by adding new technologies to milk more mileage out of traditional internal combustion gasoline engines (ICE’s). One approach is equipping more small engines with turbochargers to maintain good fuel economy without sacrificing performance. And the new wave of small cars also are arriving with smaller engines, which naturally also helps the cause. Diesels, which boast 25%-plus higher fuel economy, have long been popular in Europe where fuel taxes are double what Americans pay. Now diesels are getting a new look in the U.S., China and elsewhere.
Using more aluminum in body structures to replace heavier steel is one approach. Land Rover, which builds relatively hefty SUVs, reports it has cut 900 lbs. from the new Range Rover by switching to the light metal in body and chassis components, enabling the downsizing of engines, brakes, fuel tanks and other systems. The result: A 25% reduction in fuel consumption and a substantially lower carbon dioxide emissions.
Numerous automakers have turned to aluminum for body and chassis components to hold down poundage. Among specific models are the Chevrolet Corvette ZR1, the BMW 6 series and the Audi R8, a pioneer in all-aluminum body structures. Aluminum, however, remains more expensive than steel. Although it has dropped from $150 a pound 10 years ago to $10 now, steel is still around $1 per pound. And, of course steel manufacturers are fighting back with lighter high strength alloys.
Space-age carbon fiber also is an attractive alternative. It weighs 60% less than steel but is five times stronger and two times stiffer. When widely used in body panels and structures it’s calculated to improve fuel economy by 30% and lower emissions from 10% to 20%. But it can cost up to $17 per pound, a major disadvantage for mainstream vehicles. High priced cars like Ferrari and Lamborghini have long featured carbon fiber panels and structures. More recently the Chevrolet Corvette has adopted a carbon fiber hood and the new BMW i3 city car’s upper body structure is made of the material.
Grede Lightweighting Solutions: SiboDur® and Lost Foam
The challenge for cast iron manufacturers like Grede that produce robust engine, drivetrain, axle, steering and other major components for light duty and commercial vehicles, is to reduce weight without sacrificing performance, durability or safety considerations.
Click to read about Grede's SiboDur® solution...
Click to read about Grede's lost foam solution...