Optimization of scale-up of KNLN piezocomposites: for flexible haptic feedback applications

In this thesis, we focus on flexible haptic feedback applications which rely on the sensation of touch to display a feedback to the user that establishes a system to user interaction. Piezocomposites made of piezoceramic and polymer phases can be used here due to their high flexibility and piezoelectric properties that enable them to deform under an electric field. A lead-free piezoceramic: KNLN-3 has been chosen as the ceramic phase due to lead-based ceramics having issues with toxicity and dielectric mismatch in composites. A flexible polymer: CFE was chosen as the polymer phase due to its high dielectric constant that decreases the dielectric mismatch to the maximum extent. The first objective of this thesis is to optimize the scale-up in production of KNLN-3 when employed as a random 0-3 composite. Thus, the production of KNLN-3 was analyzed with respect to the microstructure, purity, surface topology, poling, lithium content, precursors used and correlated with its performance in a composite. Based on this set of data, an optimized powder was obtained. The second objective of thesis was to perform mechanical tests on a composite made with this powder to obtain mechanical properties that quantify its effectiveness as a flexible haptic feedback device. From these tests, the optimized powder was seen to be the most ideal when it was employed as an R50 (0-3 composite with 50 % filler) composite with no glass fibres used during production.Aerospace Engineering | Structures and Material