General Motors scientists at the automaker’s research and development centre in Warren, Michigan, have claimed a technological breakthrough in so-called smart materials, which will be ready for series production in vehicles from as early as 2010.


These shape memory alloys and polymers can change their shape, strength, and/or stiffness when heat, stress, a magnetic field or electrical voltage are introduced. This opens new possibilities for many movable vehicle features, as shape memory alloys, and polymers in particular, ‘remember’ their original shape and can return to it.


“Smart materials will change the look and feel of our cars and trucks,” said Larry Burns, GM vice president of research & development and strategic planning. “With these new materials, functionality can be ‘programmed in’ to enable innovative designs, improved efficiency, and new and improved features that will make our vehicles more exciting to own and operate than the automobiles of the past.”


Actuators and sensors made from these materials have the potential to improve vehicle performance, fuel economy, as well as enable new comfort and convenience features. These actuators and sensors can provide significant benefits when used to replace conventional motorised or hydraulic devices by reducing vehicle mass, component size and complexity, as well as improving design flexibility, functionality and reliability.


A few example applications include active vehicle surfaces, such as spoilers and air inlets that adjust to govern airflow; improved aerodynamics and performance; as well as hood, door latch and glove compartment releases for more convenient access.


According to Alan Taub, GM executive director of research & development, smart materials are building on previous materials advances GM has introduced over the last several years.


“These new smart materials follow a long list of material applications we are already using,” said Taub. “A few examples include novel aluminium forming processes that provide enhanced body panels and lightweight, polymer nanocomposites that provide superior mechanical properties at lower cost, and magnetorheological fluids for improved chassis systems.


“The properties inherent in shape memory alloys and polymers have the potential to be game-changers in the automotive advanced materials field, eventually leading to vehicle subsystems that can self-heal in the event of damage, or that can be designed to change colour or appearance.”


Smart materials are being used in other industries in various applications including medical devices, mobile phone antennas, toys and sporting goods. GM is collaborating with HRL Laboratories and the University of Michigan in developing potential applications.


To date, GM has more than 175 US patents issued or pending based on research work and application development in the field of smart materials.