Thermal Monitoring and Control by Infrared Camera in the Manufacture of Parts With Laser Metal Deposition

Techniques included in Additive Manufacturing (FA), especially Laser Metal Deposition (LMD), are subject to variable conditions during the manufacturing process. To achieve the required homogeneity in the manufacture of 3D components layer by layer, these instabilities must be compensated by adapting the process parameters. In this work, it is proposed to use an infrared (IR) thermal camera to monitor the evolution and thermal distribution of the surface of the parts produced, throughout the LMD deposition process. On the one hand, the influence of the temperature of the component on the resulting thickness is demonstrated. On the other hand, a control system is developed and implemented based on the adaptation of waiting times in order to maintain constant thermal conditions of the surface at the time prior to the deposition of each bead. The proposed control system is validated through LMD experimentation, demonstrating an increase in geometric homogeneity and the optimization of the time required for manufacture. This study is part of a wider development on LMD monitoring and control systems and its final objective is to increase the production capacities of this technology.