GB/T 3389.6-1997 Test methods for properties of piezoelectric ceramic materials - Rectangular sheet thickness shear vibration mode
Some standard content:
UDC 621.318.612-79
National Standard of the People's Republic of China
GB 3389.682
Test methods for the properties of piezoelectric ceramicsThickness-shear vibration mode for rectangular platePublished on December 1, 1982
National Standard Implemented on November 1, 1983
WNational Standard of the People's Republic of China
Test methods for the properties of piezoelectrlc ceramicsThickness -shear vibration mode for rectanguler lateThis standard is applicable to the testing of the material properties of piezoelectric ceramics in thickness shear vibration mode. 1 Glossary of terms and symbols
UDC 621.315.
612 - 79
GB 3389.6—82
For the definitions of the terms used in this standard, see GB3389.1--82 "Common Terminology for Test Methods for Properties of Piezoelectric Ceramic Materials". For the symbols, names and units used in this standard, see the symbol table. 2 Test principle
2.1 Frequency equation
Under the condition of electrical short circuit, the frequency equation of the thickness shear vibration of the self-moving mountain is: tgx
Here, 15 is the electromechanical coupling coefficient of the original shear vibration of the pick, X is the normalized frequency, where
angular frequency (=2nfa), rad/s,
shear, m/s:
--vibrator thickness, m1
-fundamental frequency or overtone series frequency (i=1.3.5,7,), Hz1)
-other parallel harmonic frequency, Hz.
Solving equation (1), we know that the thickness shear motion electromechanical combination coefficient 15 and other related parameters of the vibrator can be determined by the overtone ratio /f1. The corresponding relationship between the overtone ratio f/f=1 and the thickness shear vibration electromechanical combination coefficient h15 is shown in Table 1. The corresponding relationship between the ratio of the overtone parallel resonant frequency to the fundamental wave parallel resonant frequency /f and the electromechanical coupling coefficient s is shown in Table 2. 2.3. Shear vibration
Thickness shear vibration is shown in Figure (1). The vibrator is polarized along the X direction. When the excitation electric field is applied along the Z direction, shear force is generated on the XY plane (Figure 1I), causing shear on the XY plane (Figure 1II). When the electric field is reversed, the X plane produces shear in the opposite direction (Figure 1). Under the excitation of the alternating electric field, the vibrator produces a shear motion of the particle displacement in the X direction, and the propagation direction of the wave is along the Y direction, so it is transverse.
National Bureau of Standards 1982-12-80 Issued
1988-11D1 Implementation
W2. 8 Measurement Overview
GB3389.6-B2
Schematic diagram of shear vibration
Polarization direction,
Mass point position sense direction:
Apply exciting electric field +
Shear vibration direction.
The overtone ratio method tests the material properties of the thickness shear vibration mode of the piezoelectric ceramic rectangular vibrator, that is, the maximum transmission frequency of the vibrator is measured by the transmission line
dynamic transmission network under the first-order approximation = f. . After measuring the fundamental frequency and overtone harmonic frequency, calculate the overtone ratio. ,/f. , check 1 to determine the combination coefficient and calculate other density parameters of the vibration. For commonly used piezoelectric ceramic materials. The resulting frequency error is within the range of 1/3. 3 Test conditions
3.1 Environmental conditions
Normal test atmospheric conditions:
20~30℃
Standard atmospheric conditions for arbitration test:
25 ± 1 c
Relative humidity
45%~75%
Relative humidity
48%~52%
86-106kPa
86~106kPa
3.2 Sample size and requirements
The sample is a rectangular piece, its length! Thickness! The ratio of the sample is 1/10, the ratio of the width is 6 to 2, and the error of the straightness between the sample directions is not more than 5". The half-line error of the full ≠ surface is not more than half of the thickness tolerance. The recommended sample size is 12×6×1mm.
3.3 Sample treatment
On the five sides of the sample vertically ten lengths! All are condensed with metal compensation as polarization treatment electrodes, and a polarization electric field is applied along the length direction. The polarization treatment shop is at room temperature, and the polarization electrode is removed. The metal layer coated on the flat surface (!) is used as the exciting electrode. 2
W3.4 Test Preparation of the sample before use
GB3389.6—82
The sample should be kept clean and coated. According to the requirements of different porcelain materials, store for a certain time after polarization and test after being placed in the environmental conditions specified in 3.1 for hours.
3.5 Requirements for testing the electric field L at both ends of the sample
Measure capacitance and dielectric loss: E5V: mm
Measure frequency skin dynamic resistance, F-mVmm.
Test method
4.1 Test of resonant frequency f and dynamic resistance R4.1.1 Test circuit (—)
The test circuit (--) is a constant voltage source transmission test circuit, as shown in Figure 2. The voltage divider R in the figure matches the output impedance of the signal generator. Generally, R\1=R\2. The value of the terminal resistance Rr2 should correspond to the dynamic resistance R of the sample, and the reference value is 5.1α. The distributed capacitance (u) between A and H is also lower than the output capacitance C of the sample. The reactance of the distributed capacitor C\1 and C? should meet the following requirements: LaCr1RTi1oCr2RT2
Constant voltage source transmission test circuit
-Signal generator,-High frequency voltmeter,-Digital frequency generator; For example, R: Voltage divider resistor, R—voltage divider resistor, rx end resistor, C—distributed capacitance. 1.2 Full test circuit (II)
The test circuit (.) is a constant current source transmission test circuit, as shown in Figure 3. The resistance of the matching resistor Rr in the figure matches the output impedance of the signal generator. The value of the current limiting resistor Rr should be much larger than the dynamic resistance R of the sample. The reference value is k. The distributed capacitance C of A--B is much lower than the capacitance C of the sample
Figure 3 Constant current source transmission test circuit
? A signal generator, · high frequency transmission meter· (a digital frequency meter, a test group, R—matching resistor: R-eye current resistance
WGB 3389.6-82
4.1.3·Test equipment and requirementsWww.bzxZ.net
Signal generator: high frequency instantaneous stability, high accuracy of the frequency to be tested, output waveform is sine wave, harmonic distortion suppression is greater than 30dB.
Frequency meter: test error is less than 1Hz, input impedance is much greater than signal generator output impedance, H does not affect the signal generator output level.
Voltmeter, input impedance is greater than 1MQ, input capacitance is less than 40pF, frequency range is higher than the frequency to be tested, high sensitivity. Shielding box and sample holder: short shielded wire is used to connect the shielding box and each instrument, the shielding box should be properly grounded, and the connector should use a universal high-frequency plug. The diameter of the center point of the bracket electrode is about 0.5, and the two centers are aligned, so that the bracket can not only firmly support the sample, but also make the sample in a free running state.
4.1.4 Measurement of fundamental series resonance frequency 1.1 Place the tested sample on the test stand, connect the test circuit, and output the voltage of the spectrum generator to keep the test electric field between the two electrodes of the sample in accordance with the provisions of Article 3.5. In the frequency band corresponding to the fundamental frequency of the thickness shear vibration of the sample, adjust the signal generator frequency so that the voltage meter at the terminal of the test circuit (--) indicates the maximum value. [The voltage meter at the terminal of the test circuit (II) indicates the minimum value) The frequency with the maximum response is the fundamental frequency of the thickness shear vibration of the sample: 16
4.1.5 Measurement of overtone series resonance frequency f.3, f, f, and measure the fundamental frequency. Then, within the test electric field range specified in Article 3.5, continue to adjust the signal generator frequency to make the voltage indicator at the terminal of the test line (-) maximum (the voltage indicator at the terminal of the test line (-) minimum), and obtain the second, fifth, and seventh overtone series resonance frequencies of the thickness shear mode of the sample. a, f.5, f.4. 1.6 Measurement of dynamic resistance RI
In 4.1.4. When the fundamental frequency of the test sample is measured by the test circuit (I), the input voltage and the terminal output voltage at the fundamental frequency of 1 are read by the voltmeter. The resonant impedance of the sample is calculated according to formula (3). Under the first-order approximation, this is the dynamic resistance R1 of the sample. tV
武: R1
dynamic resistance, 2
Test circuit (-) input voltage, V,
-Test circuit (I) terminal output voltage, V; -Test circuit (-) terminal resistance, S2. XRY:
4.2 Measurement of free capacitance C
Use a capacitance bridge with a measurement error of no more than ±1% to measure the free capacitance CT of the sample at a frequency of 1 kHz. 4.3 Measurement of sample size
Use a recording device with an accuracy of 0.01mm to measure the length of the sample!, width b, and thickness t. 5 Calculation of material parameters
6.1 Thickness shear vibration electromechanical coupling coefficient 5 The fundamental frequency of the sample measured in 4.1.4 is , and the overtone frequency of the sample is obtained by 4.1.5. 3, at ,, f, then calculate the overtone ratios f., /f., f., /f, respectively, and look up Table 2 to get the corresponding coupling coefficient. In general, the combined coefficient 5 can be calculated from one overtone ratio. The three overtone ratios of the same sample are calculated separately to get the three values and take the average value, which can improve and ensure the accuracy of the measurement and calculation results.
5. 2 The fundamental frequency and parallel resonance frequency of the sample are , at p. The fundamental frequency of the sample is obtained by 4.1.4. The overtone frequency of the sample is measured by 4.1.5. , 5, f., then, according to the coupling coefficient value obtained in 5.1, look up Table 2 to get the corresponding value, and then calculate the fundamental frequency of the sample and the overtone frequency ",, at , /. , and four parallel resonance frequencies are calculated respectively, and the average value is taken, which is the fundamental frequency parallel resonance frequency f, of the sample. 6a Thickness shear vibration frequency constant Vs
The sample thickness t is obtained from 4.3, and the sample parallel resonance frequency is calculated from 5.2. The frequency band number NgW is calculated according to formula (4). GB3889.6--82
Where: N,---thickness shear vibration frequency constant, Hz.mFe
-fundamental frequency parallel spectrum frequency, H2;
sample thickness, m.
5.4 Shear sound velocity Vs
The thickness of the sample is measured by 4.3, and the parallel resonance frequency f is calculated by 5.2, and then Vs is calculated according to formula (5): Vs-2f.-t.
Vs
Shear sound velocity of the sample, /
Fundamental frequency parallel resonance frequency, Hz,
Thickness of the sample, m.
5.5 Thickness shear vibration mechanical quality factor Q. 4
The fundamental frequency f of the sample is measured by 4.1.4, the dynamic resistance R of the sample is measured by 4.1.6, the free capacitance C of the sample is measured by 4.2, and the fundamental parallel resonance frequency f is calculated by 5.2. Then, the mechanical quality factor Q of the sample is calculated according to formula (6): fa
Where: Q…
-R1+(f,2-f11)
-thickness shear vibration mechanical quality factor, unitless: thickness shear vibration fundamental frequency, Hs:
thickness shear vibration fundamental parallel resonance frequency, Hz, sample dynamic resistance, $2
-free capacitance, F.
5. 6 Free relative dielectric band number e,
The free capacitance C of the sample is measured by 4.2, and the length of the sample is measured by 1.3! , width b, thickness t, calculate the free relative dielectric constant e,l
according to formula (7): where:
self-relative dielectric constant, e=e1/eo, unitless number; - sample self-capacitance, F,
sample thickness, m;
sample length, m,
sample width, ㎡:
vacuum dielectric constant, eg=8,85×10-12F/m. Eo-
5.7 Clamped relative dielectric band number e
The shear vibration coupling coefficient of the sample is obtained from 5.1, and the relative dielectric constant is obtained from 5.6: Then, the clamped relative dielectric constant e,1 of the sample is calculated according to formula (8):
e, =(1-h)
Where: es—
- clamped relative dielectric band number,,=e/ea, unitless: $15
Shear vibration electromechanical coupling coefficient, unitless, - free relative dielectric constant, unitless. 8
6.B Shear open circuit elastic compliance coefficient S55
The sample density P is measured according to the method specified in GB2413-81 "Measurement method for volume density of piezoelectric ceramic materials", and the parallel harmonic frequency factory is obtained according to 5.2 of this standard. , after measuring the sample thickness 1 according to Article 4.3, calculate the shear die open circuit elastic compliance coefficient S6s according to formula 9): s B
W Formula: it. Ss
GB 3389.682
Shear die open circuit elastic compliance coefficient, m3/N, - sample volume density, kn,
-test thickness, m.
5.9 Shear mode short-circuit elastic compliance coefficient S
From 5.8, we get the shear mode short-circuit elastic compliance coefficient S%. From 5.1, we get the shear mode short-circuit elastic compliance coefficient 15, and then calculate the shear mode short-circuit elastic compliance coefficient S according to formula (11):
S%=S%.(1-k)
Where: Ss
—shear mode short-circuit elastic compliance coefficient, m/N; S
—shear mode open-circuit elastic compliance coefficient, m\N, all shear mode coefficients. Unit number. (10)
5.10 Shear mode piezoelectrostatic strain constant d5
The specimen coupling coefficient 15 is obtained from 5.1, the gate dielectric constant e1 is obtained from 5.6, and the shear mode piezoelectrostatic strain band number s is obtained from 5.9. According to formula (11), the shear mode piezoelectrostatic strain constant, C:N minus m/V; - the dielectric band number, a unitless number; - the shear membrane short-circuit elastic compliance coefficient, m,; the vacuum band number, #0=8.×10, F/m.
5.11 Shear mode piezoelectric voltage constant 915
According to 5.10, the piezoelectric strain constant 15 is obtained. According to 5.6, the relative dielectric constant is obtained. Then, the shear mode piezoelectric voltage constant 915 is calculated according to formula (12):
In the formula: 95
gd?:,
- shear mode piezoelectric voltage constant, V·m/N or m\C all-transformation mode strain number, (/N or mV; relative dielectric constant, unitless number;
vacuum dielectric constant, &, =8.35×10 12F/m. Symbol table
D(superscript)
(superscript)
Specimen width
H is the volume (c ru+C,)
Distributed electric current between points A--B
Distributed electric current
Indicates the condition of shear displacement
Shear piezoelectric transformation band number
Electric field strength
Indicates the condition of short-term electric field
Maximum admittance frequency
Maximum transmission frequency
（12）
Unit (SI system)
.Serial number
S(superscript）
T(superscript）
Parallel harmonic frequency
Series spectrum resonance frequency
GB 3889.6—82
Forbidden frequency or universal frequency spectrum (i=1,3,5,7.) Fundamental frequency series spectrum vibration is referred to as fundamental frequency
Third order series frequency
Fifth order series frequency
Seventh order series harmonic frequency
Shear mode voltage band
Thickness shear modulus motor exhaustion coefficient
Specimen length
Shear modulus frequency band
Mechanical quality factor
Dynamic resistance
Voltage dividing resistance
Voltage dividing resistance
Terminal resistance
Distribution limit
Current limiting Resistance
indicates the condition of constant strain
Shear mode open circuit elastic compliance
Shear mode short circuit elastic compliance
indicates the condition of constant stress
Sample thickness
Test circuit (-) Input current
Test circuit (·) Terminal output current
Normalized frequency
Vacuum dielectric constant (e=B:85×1012F/㎡) Fire dielectric constant
Unit (SI system)
V·n/N
Special unit number
Positive unit efficiency
W seat number
frs/ fa
Open external dielectric constant
GB 3389.6—82
Continuation
Relative dielectric constant
Relative dielectric constant
Volume density
Angular coefficient
Table 1f., Relationship with s
fs/ fa
5-0007
fs/ fn | |tt | 5+0079
5:0082
5-0087
5,0096
GB 3389.6—82
Continued Table 1
ff rt | Suibiao 1
7-0247
7,0447
3-0209
5-04 39
7-0628
ka
GB 3a89.6—82
Continued Table 1
5,0804
7-1234
7-1246
Standard Search Network
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.