Overview
ISO 17859:2015 specifies a standardized measurement method for piezoelectric strain at high electric field in fine (advanced) ceramics. It is intended for characterizing high power piezoelectric devices by measuring the strain versus electric field (S–E) behavior under unipolar excitation. Key test limits are an applied electric field from 0 to 2 MV/m and a triangular waveform frequency from 0.1 to 1 Hz. The standard defines specimen preparation, measurement equipment, procedures, calibration and reporting to ensure repeatable, comparable piezoelectric strain data.
Key topics and requirements
- Scope and purpose: Determine piezoelectric strain coefficient by plotting strain vs. electric field for high-field, high-power use cases.
- Specimen requirements: Disk or quadrilateral plates with smooth surfaces; typical thickness 0.3–1.0 mm, lateral size 5–15 mm, and size/thickness ratio of about 15–25. Electrode coverage must leave the edge region free (<10% of surface). Samples must be poled and polarity marked.
- Measurement conditions: Unipolar triangular waveform (0 → Emax → 0) with Emax < 2 MV/m and frequency 0.1–1 Hz. Measure multiple cycles (record cycles 3–5) with >100 sampling points per curve.
- Equipment & accuracy: Function/signal generator, high-voltage power source (kV range), and a displacement meter with about ±10 nm accuracy (contact or non-contact sensors such as laser interferometer, capacitive sensors, inductive gauges).
- Specimen holder & environment: Low mechanical stress holder, anti-vibration stage, acoustic cover; insulation oil may be used to prevent discharge. Mobile contact geometry and holder design are specified to reduce artifacts.
- Calibration & reference sample: Calibration using a reference PZT sample (Annex A example) and verification at 1 MV/m. Results reported with three significant figures.
- Reporting: Test date, operator, specimen type, thickness, equipment, environment, setup conditions (Emax, frequency) and S–E cycle data/graphs.
Applications and users
ISO 17859:2015 is practical for:
- Materials characterization labs and R&D groups evaluating piezoelectric ceramics (e.g., PZT).
- Product development and quality control for high power piezoelectric devices, actuators, ultrasonic transducers and sensors.
- Manufacturers and test labs needing standardized S–E data for design validation, lifetime studies and comparative performance metrics.
Keywords: ISO 17859:2015, piezoelectric strain, high electric field, fine ceramics, measurement method, strain vs electric field, high power piezoelectric devices, PZT reference sample.
Related standards
Normative references cited in ISO 17859:2015 include:
- IEC 60122-1
- IEC 60483
- EN 50324-1 and EN 50324-2
These provide complementary definitions and low-power measurement methods for piezoelectric materials.