Wyniki wyszukiwania - BazTech

Ograniczanie wyników

1 Archives of Materials Science and Engineering

1 2008

Znaleziono wyników: 1

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: ferroelectric BaTiO3 powder

Sortuj według:

Ogranicz wyniki do:

Influence of electric field DC-component on AC-response of ferroelectric powder

Starzyk F., Bąk W., Kajtoch C., Gabryś M.

Archives of Materials Science and Engineering

2008

Vol. 29, nr 1

36-39

Purpose: of this work was to establish whether ac-response of freely stocked micro-granular ferroelectric matter on fringe measuring electric field depends on constant component presence VDC (or DC-Bias). Design/methodology/approach: used involves measurements of effective dielectric permittivity (and other effective dielectric quantities) by means of interdigit dielectrometry. Fringe measuring electric field was applied to BaTiO3 micro-powder by interdigit comb sensor (ICS) Netzsch of Ms25 type. ICS was driven by measuring generator with sinusoidal voltage: v(t)= VDC+VACsin(�ωt), within frequency range 20Hz-100kHz and for DC-Bias values ranging as VDC=(0-20)V. Findings: The interdigit dielectrometry was applied to measure complex dielectric permittivity, complex dielectric modulus and others dielectric functions of ferroelectric BaTiO3 powder. The influence of constant component of electric stimulus was investigated in the frequency range 100 kHz to 20 Hz. It was established that in the low frequency range constant component of electric field enhances effective dielectric permittivity, and changes two weak relaxation processes occurring in the ferroelectric micro-granular net. It turned out that effective dielectric complex modulus of this net is most sensitive quantity for application of constant component of electric stimulus. Research limitations/implications: The density solution effect is a source of small effective dielectric permittivity of micro-granular ferroelectric powder (�ε'). �Epsilon' values are being enhanced by presence of non zero VDC value. The same effect was established for effective energy loss coefficient (�ε"). The two relaxational processes connected with VDC�𕟀 seems to be a key feature of freely stocked ferroelectric matter. Originality/value: of this work relays on the fact, that this is a first report of the VDC influence on effective dielectric properties of ferroelectric micro-granular matter. It is opening the way to a new approach in modelling of effective dielectric properties of granular matter in nature and powders technology.