GB/T 37255-2018Test method for pyroelectric coefficient of materials under DC bias field (English PDF)

Foreword

This standard was drafted in accordance with the rules given in GB/T 1.1-2009.

1 Scope

This standard specifies the terms and definitions, principles, environmental conditions, equipment and equipment of the pyroelectric coefficient of materials under DC bias electric field. Product, test procedure, test data processing.

This standard is applicable to the pyroelectric coefficient measurement of pyroelectric materials such as barium titanate and lead citrate under DC bias electric field.

2 Normative references

The following documents are indispensable for the application of this document. For dated references, only dated versions apply to this document. For undated references, the latest edition (including all amendments) applies to this document.

GB/T 3389.1 iron voltage electric ceramic vocabulary

3 Terms and definitions

The following terms and definitions as defined in GB/T 3389.1 apply to this document.

4 Principle

The pyroelectric coefficient under the bias electric field is the polarization of the sample [(Pm)E] when the sample temperature changes under the action of the DC bias electric field (E). The rate of change with temperature.

When the temperature of the sample changes, the polarization changes. The free charge on the surface of the sample in the original equilibrium state cannot completely shield the bound charge.

If connected to an external circuit, the current can be measured in the circuit.

The pyroelectric coefficient measuring device under the bias electric field is shown in Fig. 1. Measure the voltage value (U) across the sampling resistor (R) with a voltmeter while recording Voltage value (U), temperature (T) and time (t). The pyroelectric coefficient under different temperature and DC bias electric fields can be obtained according to formula (1). [(pm)E].

The pyroelectric coefficient given should indicate the DC bias electric field and the measured temperature.

In the formula.

(pm) E---the pyroelectric coefficient under the electric field (E) in units of Coulomb per square meter [C/(m2·°C)];

(Pm)E---polarization intensity under electric field (E), the unit is coulomb per square meter (C/m2);

I --- pyroelectric current, the unit is An (A);

A --- sample area, the unit is square meters (m2); […]