Hybridising electrohydrodynamic and aerosol jet printing for the manufacture of functional soft structures

This thesis presents a hybrid manufacturing technique that integrates electro-hydrodynamic (EHD) deposition with aerosol jet printing for the production of soft, functional films. The combined approach overcomes the respective rheological constraints of the individual processes and provides a pathway for high resolution computer-controlled patterning. An experimental apparatus for broad investigation of EHD deposition is developed and validated, before a focussed study on e-jet printing of polydimethylsiloxane is presented. Axial resolution and surface roughness of 5μm and 0.26μm (Sa), respectively, demonstrates the potential for the technology in emerging thin film technologies, such as dielectric elastomer actuators. Aerosol jet printing of a graphene nano-platelet is used as a more robust method for producing conductive features. Characterisation and refinement enabled the production of 50μm traces with a minimum height of ~200nm. The aforementioned processes are used to produce functional demonstrators that highlight the potential of the manufacturing technology. Combining the two materials required a complimentary oxygen plasma surface treatment to improve material wetting. Elastomer actuators, resistive strain, and capacitive sensors are all produced to demonstrate the efficacy of the techniques.