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Fatigue Damage Gradients in Fatigue Damage Gradients in Cycled PiezoelectricsCycled Piezoelectrics
For PZT samples cycled under a bipolar field For PZT samples cycled under a bipolar field the degree of fatigue damage, measured as a the degree of fatigue damage, measured as a reduction in 90° domain switching, observed reduction in 90° domain switching, observed in the center is less than near the electrode’s in the center is less than near the electrode’s outer edge. Electromechanical damage that outer edge. Electromechanical damage that initially forms near the surfaces of the initially forms near the surfaces of the sample apparently shields the center of the sample apparently shields the center of the sample from damage. This occurs across a sample from damage. This occurs across a range of crystal orientations. range of crystal orientations.
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Expanding the Reach of our Graduate Student Researchers
Wonyoung Chang (left) and Hsin Yu Li are shown presenting posters on their doctoral research at the 2005 Ceramics Gordon Research Conference in New Hampshire. They and the other members of the research team will be conducting a new outreach activity in 2005-2006 with high school students from John Hope Preparatory College (http://www.jhcp.cps.k12.il.us/) in Chicago, Illinois. They will serve as technical consultants to math modeling projects conducted by the high school students. This program will be conducted in collaboration with Professor Judith Zawojewski of Illinois Institute of Technology and her graduate students.
Research Pictures
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Fatigue as a function of PositionFatigue as a function of PositionReduced degree of fatigue observed in Reduced degree of fatigue observed in the center of samples cycled under a the center of samples cycled under a bipolar field. Electromechanical bipolar field. Electromechanical damage that initial forms at the center damage that initial forms at the center of the sample and move inward shield of the sample and move inward shield the center part of the sample thus it the center part of the sample thus it experiences a lower field and is experiences a lower field and is fatigued less. This occurs across a fatigued less. This occurs across a range of Alpha angles. range of Alpha angles.
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