Reducing mass directly impacts fuel consumption and carbon dioxide emissions, and provides additional benefits related to acceleration, braking, handling, and driving comfort.
The automotive and trucking industries are increasingly using lightweight aluminum alloys and magnesium alloys for many components previously made from steel and cast iron.
According to the Aluminum Association, the use of aluminum in 2009 cars averaged 8.6 % by weight; up from 5.1% in 1990. The use of magnesium also increased during this period.
Aluminum and magnesium castings will continue to displace steel to lower vehicle manufacturing costs, to improve vehicle weight distribution, to increase the range of electric and hybrid vehicle, and to improve fuel economy.
Cast aluminum alloys offer greater design flexibility over traditional stamped and welded steel parts. Depending on part geometry, aluminum can match steel and cast iron for impact and fatigue performance.
Magnesium alloys have high damping capacity, which reduces vibrations that cause inelastic strains on a part. Low density of magnesium allows for production of thicker parts that vibrate less and thereby reduce noise. Also, the combination of high dent resistance and elevated temperature properties make magnesium alloys a good choice for many automotive applications.
Cast aluminum and cast magnesium parts often found in today’s cars and lightweight trucks include:
- Cylinder heads
- Engine blocks
- Transmission cases and components
- Electric motor housings
- Electronic housings and covers
- Steering column components
- Seating components
- Bumper components and crash tips
- Brake components.