Overview
ISO 22007-1:2024 - Plastics: Determination of thermal conductivity and thermal diffusivity - Part 1: General principles provides a concise, authoritative overview of methods used to measure thermal transport properties of polymeric materials. This third edition explains the principles behind both transient and steady‑state techniques, defines key terms (including the newly added contact resistance), and directs users to the part‑specific standards that describe the detailed test procedures. It is a guidance document rather than a step‑by‑step test method.
Key topics
- Scope and purpose: Background and selection criteria for methods to determine thermal conductivity, thermal diffusivity, volumetric heat capacity and related properties.
- Measurement modes: Distinction between transient and steady‑state methods; and contact versus non‑contact measurement approaches.
- Principal techniques covered:
- Hot‑wire and line‑source methods
- Transient plane source (TPS) method
- Temperature‑wave analysis
- Light flash method (formerly “laser flash”)
- Steady‑state methods (guarded hot‑plate, heat flow meter)
- Comparative methods for very low conductivities
- Theory and relationships: Explanation of how thermal conductivity λ relates to thermal diffusivity α through volumetric heat capacity (λ = α · ρ · cp) and introduction of thermal effusivity and other key terms.
- Measurement considerations: Importance of specimen geometry, boundary conditions, thermal contact quality (contact resistance), measurement time, and uncertainty analysis (Annex A).
- Documentation: Requirements for test reports are summarized (Clause 6); references to detailed test methods are provided.
Applications and users
ISO 22007-1:2024 is valuable for:
- Materials scientists and polymer researchers selecting suitable thermal test methods for R&D, formulation screening and thin‑film characterization.
- Test laboratories and QA/QC teams developing measurement programs for thermal management, insulation materials, composites, electronics packaging, automotive and aerospace components.
- Product designers and engineers needing to interpret or compare published thermal property data for plastics and polymer‑filled materials.
- Standards developers and calibration laboratories establishing intercomparison and uncertainty assessments.
Practical benefits include better method selection for a given material form (bulk, film, filled polymer, anisotropic specimens), improved evaluation of measurement limitations, and guidance on reporting and uncertainty.
Related standards
Keywords: ISO 22007-1:2024, thermal conductivity, thermal diffusivity, plastics, transient methods, steady‑state methods, light flash, hot‑wire, thermal transport properties.