This study proposes a new method for measuring thermal contact resistance using lock-in thermography. By using lock-in thermography with an infrared microscope, the dynamic and spatially resolved temperature behavior of the contact interface was visualized on a microscale with one measurement. In addition, a new thermal contact resistance measurement principle was constructed after solving the three-dimensional thermal conduction equation in the cylindrical coordinates by considering a periodic heat source with a Gaussian intensity distribution and the relative position of the heating point to the sample edge, in the presence of thermal resistance at the contact interface. Consequently, the discontinuous behaviors of the temperature wave, amplitude, and phase lag at the contact interface were observed on a microscale. From that discontinuity, the local thermal contact resistance was analyzed as a fitting parameter by matching the theoretical curve to the measured amplitude and phase lag. Furthermore, the simultaneous analysis of the material thermal diffusivity was demonstrated and the validity of the measurements was confirmed.

中文翻译：

---

使用微尺度锁定热成像通过周期性加热方法测量局部热接触电阻

本研究提出了一种使用锁定热成像测量接触热阻的新方法。通过使用红外显微镜的锁定热成像，接触界面的动态和空间分辨温度行为可以通过一次测量在微观尺度上进行可视化。此外，通过考虑具有高斯强度分布的周期性热源和加热点与样品边缘的相对位置，在圆柱坐标系中求解三维热传导方程后，构建了一种新的接触热阻测量原理，在接触界面处存在热阻。因此，在微尺度上观察到接触界面处的温度波、幅度和相位滞后的不连续行为。从那个不连续性，通过将理论曲线与测量的幅度和相位滞后相匹配，将局部接触热阻作为拟合参数进行分析。此外，还证明了对材料热扩散率的同时分析，并确认了测量的有效性。