Self-clearing dielectric elastomer actuators using charcoal-powder electrodes

This study found that compliant electrodes using charcoal powder enable self clearing property to dielectric elastomer actuator. Charcoal powder is applied as compliant electrodes by smearing on a 100% bi-axially pre-stretched dielectric elastomer membrane (VHB 9473), with nominal pre-stretched thickness of 62.3 μm. This DEA using charcoal-powder electrodes can sustain up 10 kV without terminal breakdown, while those using graphite or silver grease break down at slightly above 2 kV. It is noted that this DEA using charcoal-powder has maximum areal strain at about 45 % at 4 kV, beyond which the strain does not increase further for reduced electrical conductivity. The dielectric elastomer actuator using the charcoal-powder electrodes generate less actuation strain than that using the graphite. However, the former can produce a large actuation stress as it can driven to a higher driving voltage without pre-mature breakdown.