Spectral Thermography Techniques for Melt Pool Thermal Imaging in Electron Beam Additive Manufacturing

Thermal imaging of an object in a real-time mode is relevant for many technological processes, especially in additive manufacturing of metal parts. Accuracy of the obtained data on the temperature distribution determines further decisions on the selection of optimal operating modes additive manufacturing machines. Thermal monitoring of the melt pool may allow appropriate adjusting the machine parameters to reduce the risk of formation of various defect types in monoalloys and composites. This paper is devoted to the comparison of common spectral imaging techniques for in situ thermal imaging of melt pool in additive manufacturing of metal parts. We propose the significant criteria for comparative analysis of the common techniques and assessment of their applicability for real-time monitoring of electron beam additive manufacturing.