Evaluation of the in-plane thermal diffusivity of graphite sheet by laser flash method

This study investigates the in-plane thermal diffusivity of graphite sheets using the laser flash method, known for its non-contact nature and high precision. To minimize the influence of holder material, a custom alumina holder was designed specifically for in-plane measurements. Our findings demonstrate that the in-plane thermal diffusivity of graphite sheets can be measured accurately and reliably using laser flash method. The developed measurement technique effectively addresses the need for precise assessment of thermal properties in materials that are crucial for efficient thermal management. Detailed experimental procedures, including the design of the measurement holder and the in-plane thermal diffusivity results of graphite sheet of different thickness, are elaborated. The in-plane thermal diffusivity of graphite sheets was found to range from 6.71 to 7.66 m²/s, with a measurement reproducibility within 2.2% of standard deviation. Results indicate that the laser flash method, coupled with the specialized holder, offers a robust approach for accurately assessing the in-plane thermal properties of graphite sheets, making it a valuable tool for both materials research and industrial applications. The proposed methodology provides a reliable means to measure in-plane thermal diffusivity, ensuring consistency and reproducibility in experimental outcomes.