A new study, published in the journal Advanced Science and conducted by scientists from the Technion-Israel Institute of Technology and Karlsruhe Institute of Technology in Germany, demonstrates, for the first time, that gold micro-particles have “shape memory” and self-healing properties.
The research, led by by Prof. Eugen Rabkin of the Technion, examines the properties of gold micro-particles, showing that they have the ability to repair the damage caused to them and to recover their original shape. Until now, this shape memory effect has only been observed in very few metal alloys, Nitinol (Ni-Ti) for example. The Israeli and German researchers of the current study used a sharp diamond tip controlled by an atomic force microscope (AFM) to indent the gold particles with.
Galvanizing the indented particles at a temperature of 600°C (which is about 65% of the absolute melting temperature of gold) resulted in “full healing of the damage and recovery of the particles’ original shape prior to deformation”, according to the Technion website. To understand how surprising this process is, explains Prof. Rabkin, “think of spilled coffee jumping back from the floor into the cup, or a car that recovers its original shape after being totaled in an accident”.
Prof. Rabkin says that the discovered self-healing and shape memory effect in metallic nano- and microparticles “could be utilized for the design of mechanically stable and damage-tolerant components and devices at the sub-micrometer length scale”.
This discovery could lead to multiple applications: “the development of micro- and nano-robots capable of self-repair; mechanically stable and damage-tolerant components and devices; and targeted drug delivery to the specific areas of the patient’s body”.
