tailieunhanh - Ferroelectrics Physical Effects Part 3

Tham khảo tài liệu 'ferroelectrics physical effects part 3', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 70 Ferroelectrics - Physical Effects 4 . However we do not exclude presence of barium poly titanates in glass crystallization products in quantities not influencing on the end-product properties. We have observe on X-ray patterns strongly reorientation of formed barium di-titanate crystalline phase reflex Ă hkl 002 increase from 9 and become 100 and Ă likl 401 decrease from 100 to 0 curves 2 3 . 4 900-1000 C 12h casting in water 3 740 C 12h 2 680 C 12h 740 C 12h Fig. 13. XRD-patterns of the crystallized BaTiiOs glass tape samples obtained by super cooling technique curve 1- initial tape sample thermal treated at 680 C 1211 -transparent curve 2- tape sample 680 C 1211 740 C 12h -transparent curve 3- tape sample 740 C 1211- transparent curve 4- tape sample 900-1000 C 1211 casting in water 4. Ferroelectric properties of stoichiometric glasses in BaO-TiO2-B2O3 system The ferroelectric polarization - electric field hysteresis is a defining property of ferroelectric materials hl the last twenty years it has become a subject of intensive studies due to potential applications of ferroelectric thin films in nonvolatile memories. In ferroelectric memories the information is stored as positive or negative remanent polarization state. Thus the most widely studied characteristics of ferroelectric hysteresis were those of interest for tills particular application the value of the switchable polarization the difference between the positive and negative remanent polarization Pr - Pr dependence of the coercive field Ec on sample thickness decrease of remanent or switchable polarization with number of switching cycles polarization imprint endurance retention Damyanovich 2005 . Electric field induced polarization measurement was used for ferroelectric characterization of known and revealed first time new ternary BaTi BOg 2 BaiTiiBiOo BasTigBiOii BaiTiBlOy and binary BaTiiOs stoichometric compositions glass ceramics. 71 Phase Diagramm Cristallization Behavior and .