Plastic and nonmetallic article shaping or treating: processes – Including step of generating heat by friction
Patent
1992-05-29
1994-05-24
Green, Anthony
Plastic and nonmetallic article shaping or treating: processes
Including step of generating heat by friction
264 66, 501134, 501135, 501136, 501137, 501138, 501139, 423593, 423594, 423598, 423599, 423600, 313 14, F27D 702, C04B 3546
Patent
active
053146514
ABSTRACT:
An improved pyroelectric material comprises a polycrystalline material doped with at least one donor element such that the polycrystalline material has a grain size less than 10 .mu.m (or 5 .mu.m) and a Figure of Merit greater than 90 nC/(cm.sup.2.K). In the preferred embodiments the polycrystalline material is barium strontium titanate or calcium-substituted barium strontium titanate. The donor element may be Nb, Ta, Bi, Sb, Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er or a combination thereof. The material may additionally be doped with an acceptor such as Co, Cu, Fe, Mn, Ru, Al, Ga, Mg, Sc, K, Na, U, In, Mg, Ni, Yb or a combination thereof to control the resistivity. Other structures and methods are also disclosed.
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Donaldson Richard L.
Green Anthony
Kesterson James C.
Stoltz Richard A.
Texas Instruments Incorporated
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