A surgical instrument, comprising:a transducer configured to produce vibrations, said transducer comprising:a first piezoelectric element comprised of a first material having a first Curie temperature； anda second piezoelectric element comprised of a second material having a second Curie temperature, wherein said first Curie temperature is higher than said second Curie temperature； andan end effector operably coupled to said transducer, wherein said transducer is configured to produce a standing wave of vibrations in said transducer and said end effector, wherein said standing wave comprises a node and an anti-node, and wherein said first piezoelectric element is positioned closer to said node than said second piezoelectric element.
