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报告内容摘要：
    This presentation give you a story about how scientific/experimental discoveries can be transferred to industrial production. Significant progresses have been made in the development and commercialization of PMN-PT based giant-piezoelectric crystal and products since its discovery in 1996. <001>-seeded single crystals of 3”~4” diameter are successfully commercialized, especially in medical ultrasound imaging industrials. Three generations of the ferroelectric relaxor crystals of solid solutions, i.e., binary PMN-PT, ternary PIN-PMN-PT and modified ternary solid solutions with additions such as Mn, Ce and Yb, etc., The giant-piezoelectric crystal have been broadly utilized for the next generation of acoustic transduction devices. In this presentation, following a brief review on crystal growth and applications, the physical properties of the ferroelectric crystals will be discussed in terms of domain-engineering and polarization directions in context of Elasto-Piezo-Dielectric matrices for three kinds of domain-symmetry, i.e., 3m, 4mm and mm2.
    Following aspects will be discussed:Phase transformation and spontaneous polarization - opportunity for domain-engineering; Domain-engineering - Origin of the giant-piezoelectric properties of the crystals; The best cut directions for different vibration mode; Potential applications in electro-optics.
    The challenges below are still existing for future explorations:Understand the electrical coercive field Ec and enhance/stabilize the Ec; Improve the physical properties by compositional refinement and domain size control.

报告人简介：
Pengdi Han , One of the pioneers in crystal growth of large scale multi-crucible Bridgman method, is the founder of H. C. Materials Corporation in Illinois, USA. After being awarded his B.Sc in electrical engineering (1964) from Wuhan University of Technology, he joined the crystal growth group of synthetic fluorine mica in Shanghai Ceramic Institute, China. He became a Research Associate in the Research Institute of Synthetic Crystals at Beijing, China, after accomplishment of graduate studies in theory of crystal growth at Chemistry Department of Shandong University, China (1978). He was awarded three Outstanding Researches Prizes from the State Science Committee of China. He served as the Director of Department of Functional Crystals and the Member of Scientific Committee in the Research Institute of Synthetic Crystals (1979-1986). He joined in Materials Science and Engineering department as a Senior Research Scientist at the University of Illinois at Urbana-Champaign, USA (1987-1998). His research interests include crystal growth and crystal physics. He has authored more than 120 papers, two books and three patens. Since 1998, he has successfully transferred the giant piezoelectric crystal Based on PMN-PT solid solution from academic to industrial for a variety of applications.