Overview
ISO 21819-2:2018 specifies an electrical transient response method for measuring piezoelectric properties of fine ceramics (advanced/technical ceramics) under high vibration levels. The standard applies to piezoelectric fine ceramic resonators and defines how to excite a resonator with a short burst drive, short the electrical terminals, capture the transient decay of vibration velocity and current, and extract characteristic piezoelectric and mechanical parameters from those decay waveforms.
Key topics and technical requirements
- Measurement principle: apply a burst voltage near the resonator’s resonance frequency, then set terminals to short circuit and record attenuation (decay) waveforms of vibration velocity and current. Extract the fundamental resonance component to calculate amplitudes, decay constants and resonance frequencies.
- Required equipment (clause 6):
- Function generator with burst/drive-duration control.
- Power amplifier capable of frequencies ≥ 2× resonance; recommended peak outputs ≥ 200 V and ≥ 1 A, output impedance ≤ 0.5 Ω.
- Vibration velocity meter calibrated for up to ~5× the resonance frequency and velocity range ≈ 0.01–2 m/s.
- Current probe calibrated for ~5× resonance frequency and current range ≈ 1 mA–1 A.
- Digital storage oscilloscope (DSO) with sampling ≥ 10× resonance frequency, long-record capability (≥ 1 s recommended) and numerical data export.
- Test piece holder with fine electrode pins (≤ 1 mm) to support the resonator at a single contact point per electrode; optional thermocouple provision.
- Numerical analysis software for frequency analysis, instantaneous frequency/amplitude extraction and component selection.
- Specimen form and preparation (clause 7): nominal resonator dimensions are specified (example: X = 43 ± 0.2 mm, Y = 7 ± 0.2 mm, Z = 1 ± 0.05 mm) with thickness polarization and mirror-polished lateral surfaces for laser vibrometry.
- Data analysis and reporting: extract vibration/current amplitudes, decay constants and resonance frequencies; calculate piezoelectric constants, elastic compliance and mechanical quality factor as required. The standard includes analytical procedures and an example data evaluation.
Applications and users
ISO 21819-2 is intended for:
- Materials and test laboratories characterizing piezoelectric fine ceramics and resonators.
- R&D and quality engineers at manufacturers of piezoelectric resonators, sensors, actuators and ultrasonic devices who need reliable measurements under high vibrational stress.
- Test facilities validating device performance for high-vibration environments (automotive, aerospace, industrial applications).
Practical benefits include consistent, repeatable assessment of piezoelectric behavior under load while minimizing confounding effects from external fields and temperature changes.
Related standards
- Normative reference: ISO 20507 (Fine ceramics - Vocabulary).
- ISO 21819 series: other parts of the series address related high-load characterization topics.
Keywords: ISO 21819-2:2018, fine ceramics, piezoelectric properties, electrical transient response, high vibration levels, resonator measurement, vibration velocity meter, current probe, burst drive.