Researchers create material that uses magnetic fields to transform

Researchers from the Georgia Institute of Technology and Ohio State University have developed a new soft polymer material. The material is called magnetic shape memory polymer. It can use magnetic fields to transform into a variety of shapes. The team thinks that the new material could have a range of new applications from antennas that change frequencies on the fly to gripper arms for handling delicate or heavy objects.The new material was created using a mixture of three ingredients that all have unique characteristics. The mix includes two types of magnetic particles with one for inductive heat and one with strong magnetic attraction. The third is a shape-memory polymer that helps to lock various shapes into place.

The resulting material is the first that combines all of the strengths of the individual components into a single system. The system is capable of rapid and reprogrammable shape changes that are lockable and reversible. The researchers started making the material by distributing particles of neodymium iron boron and iron oxide into a mixture of shape memory polymers. When the particles were fully incorporated, the researchers molded the mixture into various objects designed to evaluate how the material performed in a series of applications.

The team created a gripper claw from a t-shaped mold of the polymer mixture. Applying a high-frequency, oscillating magnetic field caused the iron oxide particles to heat up and warm the entire gripper. That temperature rise caused the polymer to soften and become pliable. A second field then caused the gripper claws to open and close.

The shape-changing process takes only a few seconds from start to finish. The strength of the material in the locked state is enough to allow the gripper to lift objects 1,000 times its weight. Other applications were tested, and further testing will be performed in the future.