Infrared thermography uses the temperature-imaging capability of modern thermal cameras to characterize materials and detect flaws. An energy source—whether a pulse of light from a laser or flash lamp, an induction coil, or some other source—induces heat flow in a material, and the resulting temperature patterns are imaged with the thermal camera. In flash thermography, the most widely used form of quantitative thermography, a pulse of light is used as the energy source, and then the surface cooldown is imaged with the thermal camera. Calculations based on an elementary theory of 1D heat conduction can determine thickness (or, equivalently, thermal diffusivity), and nonuniformity in the cooldown will identify defects. This article reviews the methods, approaches, and models of thermography. It focuses on illustrating and identifying the materials, thicknesses, and flaw conditions under which thermography is an effective material characterization technique.

中文翻译：

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通过红外热成像评估材料

红外热成像使用现代热像仪的温度成像功能来表征材料并检测缺陷。能量源——无论是来自激光或闪光灯的光脉冲、感应线圈还是其他一些源——会在材料中产生热流，然后用热像仪对产生的温度模式进行成像。在闪光热成像（最广泛使用的定量热成像形式）中，使用光脉冲作为能源，然后使用热像仪对表面冷却进行成像。基于一维热传导的基本理论的计算可以确定厚度（或等效地，热扩散率），冷却中的不均匀性将识别缺陷。本文回顾了热成像的方法、途径和模型。它侧重于说明和识别材料，