通过瞬态深度热成像直接测量面外热导率
Transient Depth Thermography for Probing Heat Transport
浏览论文内容
中文总结 AI 辅助
研究旨在解决面外热导率测量难题，提出瞬态深度热成像方法，利用时间分辨热辐射重建温度分布，编码深度信息获取热传输动力学，在熔融石英和MgF2上验证，不确定度2 - 5%，还测了MgF2热导率，为复杂材料热表征提供通用准确框架。
中文摘要 AI 辅助
准确测量面外热导率仍具有挑战性，特别是对于多层薄膜材料，因为现有技术依赖间接的、表面敏感的可观测值。本文介绍了瞬态深度热成像，一种非接触光谱方法，利用时间分辨热辐射直接重建时空温度分布。通过利用波长相关的光学穿透深度，该技术将深度信息编码到发射光谱中，可直接获取内部热传输动力学。我们在熔融石英和MgF2上演示了该方法，与现有技术达成一致，不确定度为2 - 5%。此外，我们测量了MgF2在宽温度范围内随温度变化的热导率。瞬态深度热成像适用于块状和薄膜系统，为复杂材料的热表征提供了一个通用且准确的框架。
英文摘要
Directly probing heat propagation inside materials remains challenging because conventional measurements are predominantly sensitive to surface temperature. Depth thermography has enabled non-contact reconstruction of subsurface temperature profiles from spectrally resolved thermal radiation under steady-state conditions. Here, we extend this approach into the time domain, establishing transient depth thermography to resolve the evolution of internal temperature during heat transport. By exploiting wavelength-dependent optical penetration depth, time-resolved thermal-radiation spectra provide access to temperature as a function of both depth and time. Tracking this spatiotemporal temperature field enables direct probing of heat propagation and quantitative determination of out-of-plane thermal conductivity and interfacial thermal resistance. We demonstrate the approach in fused silica, obtaining thermal conductivity within 2% of established values, and measure the temperature-dependent thermal conductivity of MgF2 over a broad temperature range where existing data are sparse and inconsistent. Numerical simulations further demonstrate its extension to multilayer thin films for probing interfacial thermal resistance. By extending depth-resolved thermal spectroscopy from steady-state to transient heat transport, this work establishes a new optical route for non-contact characterization of thermal dynamics in bulk and layered materials.
