ISO 16859-1:2015 — Metallic materials — Leeb hardness test — Part 1: Test method

ISO 16859-1:2015 — Metallic materials — Leeb hardness test — Part 1: Test method

ISO 16859-1:2015 is an ISO International Standard that specifies the test method for determining Leeb hardness (a dynamic hardness value) of metallic materials using defined Leeb scales.

It is commonly applied where fast, portable hardness checks are needed on parts, components, and assemblies that may be difficult to bring to a bench hardness tester.

Quick definition

Document type: Test method (dynamic hardness / rebound hardness).

What it does: Standardizes how Leeb hardness is measured on metallic materials using specific Leeb scales (including HLD, HLS, HLE, HLDL, HLD+15, HLC, and HLG).

Typical outcome: A Leeb hardness value reported on the appropriate scale for the impact device and setup used.

What this standard covers

ISO 16859-1:2015 covers the procedure for performing Leeb hardness measurements on metallic materials using a Leeb impact device and a compatible hardness indicating instrument.

In practice, the method relies on an impact body striking the test surface and an instrument evaluating rebound behavior to produce a hardness number on the selected Leeb scale.

What it does not do: It does not replace product specifications or acceptance criteria. Pass/fail limits, sampling plans, and any required correlation to other hardness scales are typically defined by the relevant product standard, drawing requirement, or purchaser specification.

Why this standard matters in testing

Leeb hardness testing is widely used for rapid inspection because it can be performed with portable equipment and with minimal disruption to production flow.

When ISO 16859-1:2015 is cited, it signals that hardness results should be generated using a consistent Leeb method, scale selection, and reporting approach so results are more comparable across operators, shifts, and facilities.

Common materials, product types, or applications covered

ISO 16859-1:2015 applies to metallic materials and is commonly used for:

• Incoming inspection and sorting of metal stock or machined parts
• In-process checks where a portable hardness tester is preferred
• Field or maintenance measurements on installed equipment (when access and geometry allow)
• General verification of heat-treatment consistency when a rebound method is acceptable for the product and surface condition

Because Leeb hardness is sensitive to test surface condition and part support/stiffness, the suitability of this method is often driven by part geometry, mass, surface finish, and access to the test location.

Common test or verification workflow

A typical ISO 16859-1-oriented workflow includes:

• Selecting the appropriate Leeb scale and impact device for the application
• Preparing and evaluating the test surface condition so readings are repeatable for the material and location
• Positioning and supporting the part so the impact event is stable and representative
• Taking multiple readings per location as required by the controlling inspection plan
• Reporting results with the correct Leeb scale designation and any relevant test conditions required by the cited procedure

Where traceability is required, verification and calibration activities are usually controlled through the companion parts of ISO 16859 that address device verification and reference test blocks.

Equipment commonly used for this standard

ISO 16859-1:2015 typically points to portable Leeb hardness testing systems rather than a stationary universal testing machine or bench hardness frame.

Common equipment: Leeb hardness tester (display/instrument) plus a compatible impact device for the desired Leeb scale, along with suitable supports/anvils or fixturing to stabilize the test piece.

Common accessories: Reference materials/blocks used for routine checks (as required by your quality system), surface preparation tools appropriate for the product (without altering the part beyond what is permitted), and positioning aids for consistent impact direction and contact.

If you are selecting a system for mixed part sizes, different alloys, or restricted-access test points, you can request a detailed quote for an equipment configuration matched to your inspection workflow.

How to read this designation or revision

ISO 16859-1:2015 identifies:

• ISO as the issuing standards body
• 16859 as the standard number for the Leeb hardness test series
• -1 as Part 1 (the test method)
• :2015 as the publication year of that edition

Because Leeb hardness testing depends on the specific scale and device setup, it is good practice to specify the exact part number and edition year in test plans and purchase requirements.

Related standards, methods, or frameworks when useful

ISO 16859 is a multipart series. In addition to Part 1 (test method), organizations commonly pair it with the parts that cover verification/calibration of the testing devices and calibration of reference test blocks to support traceability and routine control of portable hardness instruments.

If your customer or auditor calls for a specific verification schedule or reference block approach, align your procedure to the exact cited part(s) and edition(s) of ISO 16859.

Talk with us about ISO 16859-1 equipment and setup

For help selecting a Leeb hardness tester, impact device scale, and accessories that fit your part geometry and inspection requirements, talk with our team and we’ll help you scope an equipment path that matches the cited standard and your internal QC workflow.