1-3 Piezocomposites realised from small feature size, high aspect ratio, hot embossed moulds. Part II: piezocomposite fabrication

1-3 Piezocomposites offer many advantages over monolithic transducers, however replicating their fine scale structure is demanding. Viscous polymer (VP) embossing is a technique that has already been demonstrated as being capable of achieving the small feature size and high aspect ratio features that are required for piezocomposites. However, the process utilises a lost mould technique and is therefore limited by the ability to make cost effective sacrificial moulds. Hot embossing has been identified as a technique that is suitable for replicating these moulds, and piezocomposites made from them are presented here. This paper dimensionally characterises the piezocomposites through each stage of the VP embossing process. The piezocomposites described here have feature sizes of 30 mu m, volume fractions 0.5 and operating frequencies of 12.3 MHz. For the first time piezocomposites have been made by VP embossing into cost effective moulds.