We all remember liquid metal robots from the Terminator franchise. While we are decades away from building such a robot, researchers are working on liquid metal lattice materials for aerospace and robotics. As Fanghang Deng, Quang-Kha Nguyen, and PuZhang explain:
These lattice materials consist of liquid metals and elastomers organized in a core-shell manner. This hybrid design induces a shape memory effect by harnessing the solid-liquid phase transition of liquid metals. several remarkable functionalities are achieved such as recoverable energy absorption, tunable rigidity, and reconfigurable behaviors. These liquid metal lattice materials are fabricated by using a hybrid manufacturing approach, which integrates the 3D printing, vacuum casting, and conformal coating techniques.
The above GIF gives you a better idea how these materials work.
