ISO 22007-2:2022

Overview

ISO 22007-2:2022 is an international standard published by the International Organization for Standardization (ISO). This part of ISO 22007 specifies a method for determining the thermal conductivity and thermal diffusivity of plastics using the transient plane heat source (hot disc) method. Through this method, the specific heat capacity per unit volume-or volumetric heat capacity-can also be determined. The standard is suitable for applications involving various specimen geometries, both homogeneous and anisotropic materials, and enables measurements under different environmental conditions, including gaseous or vacuum at a range of temperatures and pressures.

The method detailed in ISO 22007-2:2022 is recognized for its accuracy and flexibility, providing vital performance data for plastics used in scientific, engineering, and industrial contexts where thermal management is key.

Key Topics

• Transient Plane Heat Source (Hot Disc) Method: Utilizes a self-heated sensor to produce a measured temperature increase in a sample. The subsequent analysis, based on the response of the embedded probe, yields thermal conductivity and diffusivity values.
• Versatility in Testing Conditions: The method accommodates various specimen sizes and can be used in both gas and vacuum environments, making it suitable for a broad range of operational scenarios.
• Material Types: Offers specific instructions for testing homogeneous, isotropic, and anisotropic plastics, including guidance for bulk, slab, liquid, and thin-film samples.
• Calculation of Volumetric Heat Capacity: The standard outlines procedures to calculate the specific heat capacity per unit volume, enhancing the breadth of material data that can be obtained from a single experiment.
• Range of Measurable Properties: Suitable for materials with thermal conductivity values in the range of roughly 0.010 W·m⁻¹·K⁻¹ to 500 W·m⁻¹·K⁻¹ and for thermal diffusivity in the approximate range of 5 × 10⁻⁸ m²·s⁻¹ to 1 × 10⁻⁴ m²·s⁻¹.
• Guidelines for Calibration: Detailed steps for apparatus calibration and verification ensure accuracy and repeatability across different testing setups.

Applications

ISO 22007-2:2022 delivers practical value across diverse industries and research fields:

• Material Development: Ideal for evaluating new plastics and composite materials where knowledge of thermal transport properties is crucial for product design and performance prediction.
• Quality Assurance: Supports manufacturers in controlling and certifying thermal properties of their products, ensuring compliance and meeting customer specifications.
• Thermal Management Systems: Essential for sectors like electronics, automotive, and building insulation, where thermal conductivity and diffusivity are critical parameters.
• Research and Academics: Provides a standardized method for laboratories and research institutions to measure and report thermal transport properties of plastics for comparative studies.
• Testing Anisotropic and Thin Materials: The document includes dedicated procedures for examining materials with directional properties, thin films, sheets, and even liquids, broadening its usability.

Related Standards

• ISO 22007-1: General principles for determining thermal conductivity and diffusivity of plastics, serving as a foundational reference for Part 2.
• ISO 8301, ISO 8302, ISO 472: For measuring thermal resistance or apparent thermal conductivity, especially in inhomogeneous products such as multilayer panels or slabs.

Conclusion

ISO 22007-2:2022 provides a comprehensive, reliable, and adaptable method for determining the thermal conductivity and diffusivity of plastics using the transient plane heat source method. Its wide applicability, precision, and inclusion of various material types make it an indispensable standard for industries and institutions focused on thermal property analysis of plastics and related materials.

For more detailed procedures and technical requirements, users are advised to consult the full ISO 22007-2:2022 document.