"In-Process Monitoring in L-PBF - Useful for a reliable and robust process or just an expensive feature for your AM hardware?"
After my start as a research scientist in the AM industry, process monitoring was one of my favorite topics. Pyrometry was one of the upcoming highlights and everyone wanted to see the equipped machines at formnext, so it was hard to get a spot in front of the L-PBF machines at the trade show.
Is the hype regarding in-process monitoring still visible? Thinking even further, is an adaptable process controlling the next step in getting a crowd of engineers in front of the machines at the trade show?
I've summarized just three different strategies below, but there are far more available. So, just a brief explanation of some strategies.
Acoustic: These devices are suitable for a high dynamic range to identify acoustic emissions during the laser process. If you notice a difference in your laser power or part geometry, this device is suitable to give you a trend for process signatures.
Powder bed camera: One of the most established pieces of hardware in L-PBF. Some machine suppliers offer a camera to monitor the process after exposure and deposition. Since the camera is part of your machine anyway, the software should be key to improve your analysis by using AI algorithms for powder signature qualification in the future.
Melt pool monitoring: On-axis pyrometry is suitable to give you indications of the temperature of your melt pool as a function of scan time. It is an in-depth analysis for a specific area of your part and generates a huge amount of data.
Have you used some of the explained strategies in the past? What is your favorite strategy for monitoring the L-PBF process?