Hybrid car performance can be optimized by using magnet simulation. A research project by St. Polten University of Applied Sciences in Austria has been studying the use of magnets in hybrid and electrical cars.

Hybrid and electric cars need high-performance permanent magnets to get the best out of them. However, magnetic materials currently in use require a high proportion of rare earths that are both expensive and in short supply.

The project is examining the ideal composition and structure for high-performance permanent magnets intended for use in cars to help conserve raw materials and bring down cost.

Led by materials researcher Prof. Thomas Schrefl, the “Green Cars” research project uses computer simulation methods to examine how the chemical composition and structure of a magnet influences its performance.

A typical electric or hybrid drive contains around two kilos of magnetic material, usually neodymium iron boron magnets. In order to ensure that the magnetic properties are retained even at high temperatures, the element neodymium is partially replaced by dysprosium.

However, this replacement of neodymium with dysprosium is problematic. As explained by Prof. Schrefl, "Compared to neodymium, the proportion of dysprosium in the ore is less than 10 percent. However, the high-performance permanent magnets currently used for hybrid and electric cars contain up to 30 percent dysprosium. In the long term, this will prove problematic when it comes to raw materials, particularly if you consider that, in just a few years, all new cars will be fitted with a hybrid or electric drive.”

In cooperation with the University of Sheffield in the UK, the “Green Cars” project aims to determine how the proportion of dysprosium can be reduced without compromising the thermal stability of magnets.

The computer is used to break down complex structures into individual elements so that they can be evaluated. Prof. Schrefl explains: "We reconstruct the magnet on the computer and break the granular structure of the magnet down into finite elements. By breaking down the microstructure into millions of tetrahedrons and prisms, we can recreate the spatial distribution of the metallic phases within the magnet in a computer model. We can then use the computer to simulate the effect that changes in the proportion of dysprosium have on the coercive force of the magnet."

The Green Cars project continues St. Pölten University of Applied Sciences’ tradition of using computer simulation to promote sustainable development. In 2008, the Green Dynamics project was presented with the Green IT Award and the Environmental Award of the City of Vienna. International magnet manufacturers have already expressed considerable interest in the project and have invited St. Pölten University of Applied Sciences to work in cooperation with them.