GM intros first 'smart' materials app on 2014 Corvette

Image: SMA app 2014 Corvette.jpg

The 2014 Corvette's rear cabin vent actuator (shown in red) is GM's first production application of an SMA—in this case a thin wire likely made of copper-aluminum-nickel (CuAlNi) alloy.

The 2014 Chevrolet Corvette will feature General Motors’ first production application of a shape-memory alloy (SMA)—a wire used to open and close the vent hatch that releases air from the car’s trunk area. The SMA wire, developed in-house by GM materials experts, replaces a motorized actuator and reduces component mass by approximately 1.1 lb (0.5 kg). GM vehicle engineers said use of the wire enables the trunk lid to close more easily than on the previous Corvette, where trapped air could make the lid harder to close.

SMAs typically are made of copper-aluminum-nickel (CuAlNi) alloys, nickel-titanium (NiTi) alloys, and copper-zinc-aluminum (CuZnAl) alloys. They’re considered “smart” materials because they can change their shape, strength, and/or stiffness when activated by heat (from electrical current, in the case of the Corvette), stress, a magnetic field, or electrical voltage. CuAlNi SMAs are much cheaper to make than NiTi alloys due to cheaper raw materials and less extensive processing. Their transformation temperatures—in the range of 80 to 200°C (176 to 392°F)—also are lower.

SMAs are being used increasingly in the medical and aerospace industries.They have “memory” and return to their original shape when deactivated. In the new Corvette, when activated the wire contracts and moves a lever arm to open the vent, allowing the trunk lid to close. Once the trunk lid is closed, the electrical current switches off, allowing the wire to cool and return to its normal shape, which shuts the vent to maintain cabin temperature.

Research for the SMA used on the Corvette began in late 2009, according to Paul Alexander, GM smart materials and structures researcher. He said GM has 247 patents in SMA technologies. GM Chief Technology Officer Jon Lauckner noted that SMAs enable new and improved features “at a lower cost than traditional motors and actuators.”

Lauckner and Alexander indicated that SMAs and other “smart” materials potentially could replace about 200 motorized movable parts on the typical vehicle, adding up to significant mass reduction.

Author:
Sector:
Topic:
Mentions:
Share
HTML for Linking to Page
Page URL
Grade
Rate It
4.52 Avg. Rating

Read More Articles On

2013-04-22
Kevin Woock, Henkel's Global Market Segment Manager for Automotive, explains how the Bonderite Flex Process, which uses zirconium oxide pretreatment instead of conventional zinc phosphating, enables processing of up to 85% aluminum content on vehicles vs. 25% with zinc phosphate coating.
2013-06-21
Dr. Blake Zuidema, Director of Automotive Product Applications, ArcelorMittal Global R&D, discusses with AEI the results of a comprehensive study evaluating various lightweighting materials’ abilities to help OEM fleets meet the 2025 fuel-economy target.
2013-06-24
There are many different lightweighting materials and methods, but which one to pursue? Various recent studies try to sway automakers to choose one material over another.
2013-05-03
Climate control can reduce electric-vehicle range by up to 46% from A/C usage in hot weather and up to 68% from electric heaters in cold temps. Tests of a solar glass windshield at the National Renewable Energy Laboratory show 4% savings in required A/C cooling capacity, providing an up to 1.0 mi (1.6 km) increase in vehicle range.

Related Items

Training / Education
2014-06-24
Article
2013-07-01
Training / Education
2000-01-26
Standard
1992-10-01
Article
2013-07-12