ISO 14577-6:2025

Overview

ISO 14577-6:2025 specifies the procedure for instrumented indentation testing at elevated temperature to determine hardness and other material parameters of metallic materials. Elevated temperature testing here means the indenter tip and test piece are heated above ambient while the bulk of the instrument remains at ambient, with insulating shielding around the hot zone. The standard requires traceable calibration and indirect verification of test machines when operating at elevated temperatures, and covers testing in air, inert/reducing gases, or vacuum.

Key technical topics and requirements

• Scope of testing: Measures hardness, indentation modulus and other parameters using instrumented indentation at temperatures above ambient.
• Active heating and control: Both indenter tip and test piece must be actively heated with independent feedback control and temperature measurement of each.
• Temperature assignment and uncertainty: Provides a method to estimate the contact temperature and its uncertainty. Uncertainty increases for materials with low thermal conductivity; users must decide fitness for purpose.
• Machine calibration & verification: Testing machines must be traceably calibrated and pass an indirect verification according to ISO 14577-2 when operated at elevated temperature.
• Test environments: Applicable in air, inert/reducing gas, or vacuum environments.
• Exclusions: Not applicable to systems without direct indenter tip temperature measurement, whole-instrument hot-box heating, or setups with only passive indenter heating from the heated test piece.
• Indenter considerations: Includes guidance on indenter material selection, geometry, area function, frame compliance, and reactivity (see informative Annexes).
• Procedures & reporting: Defines machine capability, temperature calibration methods, test procedure, data processing, and reporting requirements.

Practical applications and users

ISO 14577-6 is designed for laboratories and industries needing reliable mechanical property data at service-like temperatures. Typical users and applications include:

• Materials testing and R&D laboratories conducting high-temperature hardness and modulus measurements
• Quality control for aerospace, nuclear, fuel cells, cutting tools, coatings, welded joints, and high-friction/wear surfaces
• Researchers studying temperature-dependent elasto-plastic behavior and creep during indentation
• Manufacturers and certification bodies requiring traceable, repeatable elevated-temperature indentation data

Related standards

• ISO 14577-1 - Instrumented indentation test: Test Method (general procedures)
• ISO 14577-2 - Verification and calibration of instrumented indentation testing machines (mandatory for elevated-temperature verification)
• Annexes in ISO 14577-6 provide further guidance on indenter reactivity, oxidation onset temperatures, and temperature calibration procedures.

Keywords: ISO 14577-6, instrumented indentation, elevated temperature testing, hardness, indentation modulus, contact temperature, traceable calibration, ISO 14577-2, thermal conductivity, indenter tip temperature.