عنوان البحث(Papers / Research Title)
The D.C and A.C Electrical Properties Of Pb3O4Thin Film
الناشر \ المحرر \ الكاتب (Author / Editor / Publisher)
بهاء حسين صالح ربيع الحسيني
Citation Information
بهاء,حسين,صالح,ربيع,الحسيني ,The D.C and A.C Electrical Properties Of Pb3O4Thin Film , Time 5/10/2011 8:10:23 AM : كلية التربية للعلوم الصرفة
وصف الابستركت (Abstract)
The D.C and A.C Electrical Properties Of Pb3O4 ThinFilm
الوصف الكامل (Full Abstract)
The D.C and A.C Electrical Properties Of Pb3O4Thin Film
In order to fulfill the requirements of polymer industry many developers usually blend polymers together in order to reach an optimum balance of properties, this approach allows high flexibility in property adjustment and avoids development of new macromolecules which is generally long and expensive compared to polymer alloying [Mohammed, 2007]. A vigorous development of polymer composite and extensive utilization of polymer materials in technology have led to the polymer composites [Wenderlinch;1973]. The importance of polymers is mainly because polymers are still regarded as a cheap alternative material that is manufactured easily.
The intensive use of polymer in broad use has led to the development of materials for specific applications namely composites [Comelio et al, 1996]. Recently polymer matrix-ceramic filler composites receive increased attention due to their interesting electrical and electronic properties, Integrated decoupling capacitors, angular acceleration accelerometers, acoustic emission sensors and electronic packaging are some potential applications. Ceramic materials are typically brittle, possess low dielectric strength and in many cases are difficult to be processed requiring high temperature. On the other hand, polymers are flexible, can be easily processed at low temperatures and exhibit high dielectric break down fields[kontos, et al , 2007].
Ahmed and Marwa, in(2010) studied the effect of Lithium Fluoride content on D.C electrical properties of poly-methyl methacrylate. The D.C electrical conductivity of the PMMA increased by increasing of LiF concentrations and temperature. The activation energy decrease with increasing filler concentration The present work deals with the effect of alumina additive on the D.C and A.C electrical properties of poly-methyl methacrylate composite. Experimental work
The materials used in the paper is poly-methyl methacrylate as matrix and alumina as a filler. The electronic balanced of accuracy 10-4 have been used to obtain a weight amount of alumina powder and polymer powder .These mixed by Hand Lay up and the Microscopic Examination used to obtain homogenized mixture .The weight percentages of Al2O3 are ( 0, 15,25,35 and 45) wt.%. The Hot Press method used to press the powder mixture. The mixture of different Al2O3 percentages has been compacted at temperature 165oC under a pressure 100 bar for 10 minutes .
Its cooled to room temperature , the samples were disc shape of a diameter about 15mm and thickness ranged between (1.08-1.32)mm. The coating unit (Edward coating System E3C6A) has been used for deposition of thin film Aluminum electrode on both sides of each sample . The resistivity was measured over range of temperature from (30 to 70)oC using Keithly electrometer type (616C) .The volume electrical conductivity defined by :
Where :
A = guard electrode effective area.
R = volume resistance (Ohm) .
L = average thickness of sample (cm) .
In this model the electrodes have circular area A= D2?/4 where D= 0.5 cm2 .
The dielectric properties of PMMA- Al2O3 composites were measured using (Agilent impedance analyzer 4294A ).
In the frequency(f) range (25×102-5×106) Hz at room temperature. The measured capacitance, C(w) was used to calculate the dielectric constant ,?(w) using the following expression:
(2) ?(w) =C(w)
Where d is sample thickness and A is surface area of the sample . whereas for dielectric loss ?"(w): : ?"(w) = ?(w) × tan?(w) (3)
Where tan?(w) is dissipation factor . The AC conductivity ?ac Can be calculated by the following equation :
(4)
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