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The nature of the pyroelectric properties of the composite %Ca/Epikote 828 with 50/50 and 60/40 vol% was reported in the fifth interim report. The present report provides an account of the preparation of pure lead titanate (H) and calcium modified lead titanate (%Ca) by the Sol-Oel process. X-ray Spectroscopic Structural Analysis and Differential Scanning Calorimetric (DSC) studies of the ceramic grains produced by this technique were made and the results are given in this report. The sot-gel method for preparation of ferroelectric ceramics can offer many advantages over conventional processing techniques. Ceramics produced via the sol-gel method show high degrees of purity and homogeneity, can produce fme powders as well as being able to be formed into a variety of structures and they possess the ability to be processed at lower temperatures.

Described is the development of polymer piezoelectric devices with sufficient electrical output in response to impact to demonstrate the feasibility of using polymer elements in place of ceramic elements in ordnance fuze systems. To satisfy this requirement, piezoelectric polymer elements have been constructed capable of providing at least 0.3 mJ into a 4-ohm load, in response to a force of 89 kN (10 tonsf). Total activities of up to 360 pC/N have been achieved from elements built up from 30 sheets of 25-micrometers poly(vinylidene fluoride). Test methods developed to characterize both single-sheet and total-element activities are described, as are poling procedures and details of element construction. Mathematical analyses of polymer piezoelectric output into resistive-capacitive loads are presented for static and dynamic cases. Experimental results and theoretical predictions are shown to be in agreement to within the 10% estimate of measurement accuracy. (Author)