The quality control of manufactured parts is usually divided between Destructive and Non-Destructive technics.
The former, of which tensile tests, hardness tests, metallographic tests are part of, cannot by nature, be applied to all manufactured parts. Conversely, relevant Non-Destructive technics (Archimedes density measurements, CT-scan, FPI) for additively manufactured parts, are too expensive to be utilized on a large scale production (CT-scan) or not sensitive enough to detect a low number of defects (Archimedes measurements). In this context, performing a cost-effective, systematic and performant quality control on parts remains a challenge.
The combination of DMP Monitoring for the in-situ process data collection and DMP Inspection for the data analysis and interpretation offers a quality control solution viable on a large scale while remaining economical and performant.
The solution envisioned to manage the quality of parts in a seamless way relies on the combination of DMP Monitoring for the data process collection and DMP Inspection for the data treatment. The result, a merge between the CAD part and the events detected, is readily accessible in 3DXpert®, the all in one additive software solution. The data collection through DMP Monitoring is made possible by two sensors based systems : DMP Vision and DMP Meltpool. The former, focusing on the powder bed quality, is implemented using a high speed and high-resolution industrial camera. The latter relies on the use of photodiodes recording meltpool data at 50 kHz. For a given layer, DMP Monitoring will capture two sorts of data :
- Powder bed images captured after powder deposition and after the laser scanning of the considered layer, for the purpose of assessing the homogeneity of the powder deposition and quality of the scanned surface.
- Spatially integrated light emission from the meltpool during the powder bed scanning. The emphasis here is on the detection of meltpool abnormalities following a defined set of rules (e.g. abrupt fluctuation in the signal recorded from a single scan vectors).
The DMP Inspection tool allows the user to access process-induced defects based on the melt pool signature or the powder bed quality.
Based on both metrics, the user can identify an extensive number of possible defects (lack of fusion, dross, warping, spatters, powder lumps, and coater lines). In order to ease the severity assessment of such defects, a color-coded scale and the location of the considered defects are displayed. With such built-in functions, DMP Inspection eases the quality assessment of L-PBF-induced defects and allows for a fast assessment of the quality of printed parts.