Piezoelectric hydrophones from optimal designs, Part I: fabrication

Complex three-dimensional optimal designs for improved piezoelectric hydrophones were being realized in lead zirconate titanate piezoelectric ceramics using an indirect solid freeform fabrication technique employing lost molds to define internal void spaces. Lost molds were fabricated by wax-based ink jet deposition, and replicated in PZT ceramic using acrylate suspension polymerization. The physical size of the object is determined by the finest feature present in the design, and by the resolution of the ink jet device. Arrays with 125 repeat units were fabricated with a fidelity of 0.9% in placement of features. The Indirect Solid Freeform Fabrication technique is described in detail.