Overview
EN ISO 16859-2:2015 - "Metallic materials - Leeb hardness test - Part 2: Verification and calibration of the testing devices" (CEN/ISO) defines how to verify and calibrate Leeb hardness testing instruments. It specifies direct and indirect verification methods for instruments used to determine Leeb hardness (per ISO 16859‑1), and explains when each method should be applied. The standard also describes required conditions (e.g., verification temperature of (23 ± 5) °C) and the content of verification reports or calibration certificates.
Key topics and technical requirements
- Direct verification (component-level checks)
- Verifies individual instrument performance parameters against specified limits.
- Checks include: mass and geometry of the impact body, geometry and hardness of the indenter ball, geometry of the support ring, and impact velocity.
- Calibration reference parameters for common impact device types (D, S, E, DL, D+15, C, G) are provided (examples: typical impact velocities ~2.05 m/s for D/S/E types; indenter Vickers hardness around 1600 HV ±100 for most types).
- Instruments used for verification must be traceable to national measurement standards.
- Indirect verification (system-level checks)
- Uses hardness measurements on reference test blocks calibrated in accordance with ISO 16859‑3 to check overall instrument performance (testing in the direction of gravity).
- The indirect method can be used alone for periodic in-service performance checks.
- General conditions
- Instruments must be properly set up per manufacturer’s instructions prior to verification (impact body installation, support ring mounting, cable connections, indicator settings).
- Reporting and uncertainty
- The standard requires documentation of verification results and addresses measurement uncertainty and intervals between verifications.
Applications and users
This standard is practical for organizations that perform or rely on Leeb hardness testing, including:
- Calibration laboratories and metrology services performing verification/certification of hardness testers.
- Quality assurance and inspection teams in metalworking, automotive, aerospace, and manufacturing industries.
- Non‑destructive testing (NDT) technicians verifying portable Leeb hardness devices in the field.
- Instrument manufacturers developing or supporting Leeb impact devices.
Use cases: routine in-service performance checks, initial type/calibration verifications, acceptance testing after repair, and ensuring traceability to national standards.
Related standards
- ISO 16859‑1 - Leeb hardness test: Test method
- ISO 16859‑3 - Calibration of reference test blocks (used for indirect verification)
- ISO 6507‑1 - Vickers hardness test (referenced for indenter hardness testing)
Keywords: EN ISO 16859-2:2015, Leeb hardness test, verification and calibration, Leeb hardness testing devices, direct verification, indirect verification, reference test blocks, calibration certificate, impact device, indenter ball.
