Mitsubishi Electric confirms self-recovery graphite

Mitsubishi Electric has confirmed “the world’s first self-recovery property in highly oriented pyrolytic graphite (HOPG)”, a discovery it claims could extend the operational lifetime of micro electro mechanical systems (MEMS) used in automotive safety systems.

The research, conducted jointly with Kyoto University’s Solid Mechanics Laboratory, found that HOPG specimens soften as load cycles increase but recover their mechanical properties, including hardness, over time.

The two organisations developed a new testing method in which micro-scale HOPG specimens are subjected to repeated bending loads to induce shear deformation. The discovery suggests HOPG could be used as a vibration absorption mechanism capable of recovering from vibration-induced fatigue.

Demand for MEMS, including accelerometers and pressure sensors, is growing as autonomous driving and wearable technology advance. Van der Waals-layered materials such as HOPG are considered promising for MEMS applications due to their light weight, flexibility and high strength, but their fatigue properties under repeated loading had not previously been explored.