1. College of Automation, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu 211106, China
2. The Academy of Armored Forces Engineering, Chinese Peoples Liberation Army, Beijing 100072, China
Abstract:To measure the in-plane directional thermal diffusivity of the conductive material, a new method called pulsed eddy current thermography is proposed. Eddy current along a certain direction is induced on the surface of the conductive material by using an inductive pulsed line excitation to achieve local heating. Under non-steady conditions, simply changing the relative position between the sample and the coil can quickly and non-destructively measure the diffusivity in the vertical direction of the coil. The in-plane heat conduction and the Gaussian temperature distribution are analyzed on the condition of the inductive pulsed line excitation. The AISI304 stainless steel, pure iron, and pure nickel are measured and the measurement results are in accordance with the literature values, all the deviations are less than 9.0% and the relative extended uncertainty is 3.18%,3.72% and 3.70% respectively.
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