SU1515122A1 - Method of determining dielectric permettivity of materials - Google Patents

Abstract

The invention relates to a measurement technique and can be used to determine the dielectric constant of samples with a small surface conductivity. The aim of the invention is to improve the measurement accuracy and speed up the measurement process. A device implementing the method contains stationary measuring electrodes 1 and 2, two identical dielectric samples 3 and 4 having the same dimensions with electrodes (D is the distance between electrodes 1 and 2, D / 2 is the thickness of each of the two samples). While the electrodes 1 and 2 are connected to the meter 5 capacity, and samples 3 and 4 are placed between the electrodes. The method allows to simplify the process of measuring the dielectric constant, as well as to eliminate the effect of capacitance measurement error, which occurs when the position of the moving electrode changes in the prototype method. 1 il.

Description

one

(21) 4255164 / 24-21

(22) 06/02/87

(46) 10/15/89. Bul № 38 (72) Ch.O.Kajar and T.B.B.Rzayev

(53) 621.317.75 (088.8)

(56) USSR Copyright Certificate No. 675375, cl. G 01 R 27/2, 1977.

USSR Author's Certificate No. 1195286, cl. G 01 R 27/26, 1-984.

(54) METHOD FOR DETERMINING THE DIELECTRIC PERMITTIVITY OF MATERIALS

(57) The invention relates to a measurement technique and can be used to determine the dielectric constant of samples with a small surface conductivity. The aim of the invention is to improve the measurement accuracy and speed up the measurement process. The device implementing the method contains stationary measuring electrodes 1 and 2, two identical dielectric samples 3 and 4, having the same dimensions with the electrodes (d is the distance between electrodes 1 and 2, d / 2 is the thickness of each of the two samples). While the electrodes 1 and 2 are connected to the meter 5 capacity, and samples 3 and 4 are placed between the electrodes. The method allows to simplify the process of measuring the dielectric constant, as well as to eliminate the effect of capacitance measurement error, which occurs when the position of the moving electrode changes in the method of the prototype. 1 il.

about b

(L

ate

01

to to

electrodes 1 and 2, - - the thickness of each

31515

The invention relates to the measurement of electrical quantities and can be used to determine the dielectric constant of samples with low surface conductivity.

The aim of the invention is to improve the measurement accuracy and speed up the measurement process.

The drawing shows a block diagram of the device, explaining the essence of the method for measuring the dielectric constant.

The device contains stationary measuring electrodes 1 and 2, two identical dielectric samples 3 and 4, having the same dimensions with electrodes, d is the distance between

d 2

It consists of two dielectric samples. Stationary electrodes 1 and 2 are connected to the capacitance meter 5, and dielectric samples 3 and 4 are placed between electrodes 1 and 2.

The device works as follows.

obd)

The capacitance is determined when there are two samples between electrodes 1 and 2. One specimen 4 is removed and the capacitance between electrodes 1 and 2 with sample 3 and an air gap is determined.

d equal to the sample thickness -. Take off

the second sample 3 and determine the value of the capacitance between the electrodes 1 and 2 with an air gap equal to the thickness of the two samples d.

. The magnitude of the dielectric constant of a bo sample is determined by the results of measured capacitances by the formula

e, CiL I-CiL

Cg, - С „

where C is the capacitance between the electrodes with two identical samples;

C, is the capacitance between the electrodes with the sample and the air gap equal to the sample thickness;

C is the capacitance between the electrodes with an air gap equal to the thickness of two identical samples. Thus, the dielectric potential% is determined only by the sign Q

five

0

g

ABOUT

five

five

capacitance and does not depend on the geometric dimensions of the measuring condensate, the use of two identical samples and fixed measuring electrodes allows not only to simplify the method of measuring the dielectric constant and its technical realization, but also to eliminate the effect of measurement error of the capacitance arising from changing the position of the mobile electrode in the prototype method.

Claims (1)

Invention Formula The method for determining the dielectric constant of materials, which consists in measuring the capacitance between the electrodes, the gap between which is completely filled with the material under study, measuring the capacitance between the electrodes with an air gap, and measuring the capacitance between the electrodes with a thickness of the material under study between them equal to half the gap between the electrodes, and having the same size with it, -1PO area, characterized in that, in order to improve the measurement accuracy and speed up the process from measurement, the measurement of the capacitance between the electrodes with the full filling of the gap between them is carried out when placing the second sample similar to the first one, and the measurement of the capacitance between the electrodes with an air gap is carried out with equal thickness of the two samples of the material under study and calculate the dielectric constant of the sample and the material under study according to the formula 5, eii-i-iii-,  3 " - with, where Pa is the capacitance between electrodes with two identical samples; .d, - - WITH". - capacitance between electrodes with the sample and the air gap equal to the thickness of the sample; Sd is the capacitance between the electrodes with an air gap equal to the thickness of two identical samples.