In an effort to accelerate the industrialization and adoption of metal additive manufacturing (MAM) processes, fabricators have been pursuing in-situ process monitoring with the help of weld cameras. For example, Xiris recently collaborated with the Multi-Scale Additive Manufacturing (MSAM) lab at the University of Waterloo, Waterloo, Canada, on a range of vision data acquisition and analytics projects for observing the laser-material interaction in powder bed AM machines. A Xiris high dynamic range weld camera was deployed to try to capture material ejecta phenomena during the laser powder bed fusion process as a possible low-cost process quality metric.
The Results
Although preliminary, the results showcased that the camera system is capable of detecting plasma plume size and orientation as a function of the beam path, to gauge the interaction between the gas flow inside the machine and the laser scan path. The preliminary image analysis indicates that some scan paths result in larger plumes, which can be indicative of potential defects.
The team has also looked at feature detection methods using image processing for isolating the melt pool material ejections in the field of view to extract the frequency, orientation and size of these ejecta. The initial results indicate that the vision data may be used to detect keyhole sputter that can be correlated to part defects. However, further studies are required to ensure the robustness of such results.
Image Analysis of the Initial Testing at University of Waterloo
Xiris plans to further develop quality and process control tools to users of powder bed AM machines so that they can improve their process characterization. As our initial results show, the Xiris HDR camera has significant potential for monitoring the melt process in powder bed AM processes.
To learn more about how the Xiris Weld Cameras can be used in additive manufacturing applications, check out our related blogs.
