PTC yog hais txog qhov tshwm sim ntawm cov thermistor lossis cov khoom siv nrog kev nce siab hauv kev ua haujlwm thiab qhov zoo ntawm qhov kub thiab txias ntawm qee qhov kub, uas tuaj yeem siv tshwj xeeb los ua qhov ntsuas kub tsis tu ncua. Cov khoom siv yog lub cev sintered nrog BaTiO3, SrTiO3 lossis PbTiO3 ua cov khoom tseem ceeb, uas muaj me me ntawm oxides xws li Nb, Ta, Bi, Sb, y, La thiab lwm yam oxides ntxiv los tswj lub atomic valence kom nws. semiconducting. Qhov no semiconducting barium titanate thiab lwm yam ntaub ntawv feem ntau hu ua semiconducting (bulk) porcelain; Nyob rau tib lub sijhawm, oxides ntawm manganese, hlau, tooj liab, chromium thiab lwm yam additives yog ntxiv los ua kom qhov kub thiab txias coefficient ntawm kev ua haujlwm zoo.
PTC yog hais txog qhov tshwm sim ntawm cov thermistor lossis cov khoom siv nrog kev nce siab hauv kev ua haujlwm thiab qhov zoo ntawm qhov kub thiab txias ntawm qee qhov kub, uas tuaj yeem siv tshwj xeeb los ua qhov ntsuas kub tsis tu ncua. Cov khoom siv yog lub cev sintered nrog BaTiO3, SrTiO3 lossis PbTiO3 ua cov khoom tseem ceeb, uas muaj me me ntawm oxides xws li Nb, Ta, Bi, Sb, y, La thiab lwm yam oxides ntxiv los tswj lub atomic valence kom nws. semiconducting. Qhov no semiconducting barium titanate thiab lwm yam ntaub ntawv feem ntau hu ua semiconducting (bulk) porcelain; Nyob rau tib lub sijhawm, oxides ntawm manganese, hlau, tooj liab, chromium thiab lwm yam additives yog ntxiv los ua kom qhov kub thiab txias coefficient ntawm kev ua haujlwm zoo. Platinum titanate thiab nws cov kev daws teeb meem yog semiconductorized los ntawm cov khoom siv hluav taws xob zoo tib yam thiab kub kub sintering kom tau txais cov ntaub ntawv thermistor nrog cov yam ntxwv zoo. Nws qhov kub coefficient thiab Curie point kub sib txawv nrog cov muaj pes tsawg leeg thiab sintering tej yam kev mob (tshwj xeeb tshaj yog txias txias).
Barium titanate crystals belongs rau cov qauv perovskite. Nws yog cov khoom siv ferroelectric, thiab cov ntshiab barium titanate yog cov khoom siv insulating. Tom qab qhov sib ntxiv ntawm cov kab tsis tshua muaj hauv ntiaj teb rau barium titanate thiab kev kho cua sov kom zoo, qhov kev tiv thaiv tau nce zuj zus los ntawm ntau qhov kev txiav txim siab ntawm qhov ntsuas kub ntawm Curie, ua rau PTC nyhuv, uas zoo ib yam nrog ferroelectricity ntawm barium titanate crystals thiab cov khoom ntawm Curie kub. nyob ze cov kev hloov pauv. Barium titanate semiconductor ceramics yog cov ntaub ntawv polycrystalline nrog kev sib tshuam ntawm cov nplej. Thaum lub semiconductor ceramic nce mus txog qhov ntsuas kub lossis qhov hluav taws xob, cov ciam teb hloov pauv, uas ua rau muaj kev hloov pauv tsis zoo.
Cov nyhuv PTC ntawm barium titanate semiconductor ceramics los ntawm cov ciam teb (grain boundaries). Rau kev ua cov khoom siv hluav taws xob, qhov sib cuam tshuam ntawm cov khoom ua raws li qhov muaj feem cuam tshuam. Thaum qhov kub thiab txias tsis tshua muaj, vim qhov kev txiav txim ntawm lub teb hluav taws xob hauv barium titanate, cov electrons tuaj yeem yooj yim dhau los ntawm qhov cuam tshuam, yog li tus nqi kuj yog me me. Thaum qhov kub thiab txias tau nce nyob ze ntawm Curie point kub (xws li qhov kub thiab txias), qhov hluav taws xob sab hauv raug puas tsuaj, uas tsis tuaj yeem pab ua cov khoom siv hluav taws xob hla lub peev xwm thaiv. Qhov no yog qhov sib npaug ntawm qhov muaj peev xwm ua rau muaj kev cuam tshuam thiab muaj kev tawm tsam sai sai, ua rau PTC nyhuv. Lub cev qauv ntawm PTC nyhuv ntawm barium titanate semiconductor ceramics suav nrog Haiwang nto barrier qauv, barium vacancy qauv thiab superposition barrier qauv ntawm Daniels li al. Lawv tau piav qhia tsim nyog rau PTC cov txiaj ntsig los ntawm ntau yam.
Post lub sij hawm: Mar-09-2022
