Session: 04-01 Emerging Technologies: Smart AM

Paper Number: 90188

90188 - Thermographic Analysis Method of Parts Produced With Wire Arc Additive Manufacturing 

Wire arc additive manufacturing (WAAM) is one of the most promising techniques when compared to other additive manufacturing (AM) technologies due to its high deposition rates and the capability to produce parts with unlimited size preserving their structural integrity. The implementation of monitorization systems using Non-Destructive Testing (NDT) to ensure the repeatability and stability of the process, should be applied to the production lines to assure the inspection of the parts in real-time, reducing the number of rejected parts. Of the NDT's nowadays available, thermography has shown to be one of the most promising monitoring techniques for WAAM processes due to its high thermal sensibility for defect detection, easy implementation, and low complexity to use. In this paper, an enhanced thermographic analysis method of the WAAM process is presented. Various deposition tests were performed varying the main processing parameters and the correlation between the changes made to the parts and the corresponding behaviour of the thermograms were successfully analysed. The post-processing analysis method was performed using the MATLAB incorporated functions, to create the temperature gradients and image processing algorithms in order to extract and classify the characteristic area of the thermal profile in the deposition area. Histogram analysis and a pre-processing filter was applied to enhance the quality of the image. The segmentation by the binarization of the image was carried out, avoiding reflections appearances with the bwpropfilt function in a predefined region of interest. Lastly, different stages of the process and the most reliable gradient vector to monitor the process, preserving its shape and dimension as the number of layers increases were identified. This method showed promising results in the feature extraction for AM processes, validating the use of this technology in an inspection system.

Presenting Author: André Cabrita Instituto de Soldadura e Qualidade

Presenting Author Biography: Currently, André Cabrita is working in Instituto de Soldadura e Qualidade as a Researcher in Non-destructive testing techniques. A graduate Master's Degree student in Physics Engineering in the Faculty of Sciences of the University of Lisbon with a Master's thesis carried out in partnership with Instituto de Soldadura e Qualidade with an opportunity to do an internship as a Researcher in additive manufacturing technologies in the same institution. His growing interest in Non-destructive testing techniques, computer vision systems, and data analysis made him pursue a venture through these up-and-coming technologies to incorporate and automatize additive manufacturing processes.

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