I have issues with these inventions.
First, PZT is not a metal and not capable of conducting; it is a piezoelectric ceramic dielectric. It needs a metallic coating to work. Second, if you do plate it with a metal to make a piezoelectric transducer, it has a high capacitance and will need lots of power.
“it appears the Navy relied on an affidavit from an expert, which the Examiner initially argued wasn’t sufficient ...”
How about the opinion of another expert in the field (me).
My credentials: https://www.amazon.com/Ultrasound-Piezoelectric-Physics-Engineers-Applications/dp/1793995389/ref=tmm_pap_swatch_0?_encoding=UTF8&qid=1552143786&sr=8-3
These inventions are flim-flam and won’t work.
Impressive. You literally wrote the book on PZT.