TY  - JOUR
A1  - Oster, Simon
A1  - Fritsch, Tobias
A1  - Ulbricht, Alexander
A1  - Mohr, Gunther
A1  - Bruno, Giovanni
A1  - Maierhofer, Christiane
A1  - Altenburg, Simon
T1  - On the registration of thermographic in situ monitoring data and computed tomography reference data in the scope of defect prediction in laser powder bed fusion
JF  - Metals : open access journal
N2  - The detection of internal irregularities is crucial for quality assessment in metal-based additive manufacturing (AM) technologies such as laser powder bed fusion (L-PBF). The utilization of in-process thermography as an in situ monitoring tool in combination with post-process X-ray micro computed tomography (XCT) as a reference technique has shown great potential for this aim. Due to the small irregularity dimensions, a precise registration of the datasets is necessary as a requirement for correlation. In this study, the registration of thermography and XCT reference datasets of a cylindric specimen containing keyhole pores is carried out for the development of a porosity prediction model. The considered datasets show variations in shape, data type and dimensionality, especially due to shrinkage and material elevation effects present in the manufactured part. Since the resulting deformations are challenging for registration, a novel preprocessing methodology is introduced that involves an adaptive volume adjustment algorithm which is based on the porosity distribution in the specimen. Thus, the implementation of a simple three-dimensional image-to-image registration is enabled. The results demonstrate the influence of the part deformation on the resulting porosity location and the importance of registration in terms of irregularity prediction.
KW  - selective laser melting (SLM)
KW  - laser powder bed fusion (L-PBF)
KW  - additive
KW  - manufacturing (AM)
KW  - process monitoring
KW  - infrared thermography
KW  - X-ray
KW  - micro computed tomography (XCT)
KW  - defect detection
KW  - image registration
Y1  - 2022
U6  - https://doi.org/10.3390/met12060947
SN  - 2075-4701
VL  - 12
IS  - 6
PB  - MDPI
CY  - Basel
ER  -