A5037580214- Additive Manufacturing Materials and Processes
- Welding Techniques and Residual Stresses
- Laser Material Processing Techniques
- Additive Manufacturing and 3D Printing Technologies
- High Entropy Alloys Studies
- Laser-induced spectroscopy and plasma
- Manufacturing Process and Optimization
- Advanced Surface Polishing Techniques
- Recycling and Waste Management Techniques
- Surface Treatment and Residual Stress
- Nonlinear Optical Materials Studies
- Surface Roughness and Optical Measurements
- Dental materials and restorations
- Metallurgical Processes and Thermodynamics
- Medical Coding and Health Information
- Engineering Technology and Methodologies
- Analytical chemistry methods development
- Electron and X-Ray Spectroscopy Techniques
Maastricht University Medical Centre
2025
Inspire
2015-2016
ETH Zurich
2015-2016
This paper compares three distinctive sensors for laser powder bed fusion metal additive manufacturing process monitoring. A microphone airborne acoustic emissions, an on-axis two-colour pyrometer melt pool temperature measurement and off-axis thermographic camera are simultaneously applied. They challenged with a large build area to investigate their robustness sensitivity. does not assess the sensors' ability detect specific flaws, but instead gives common ground comparison of general...
Nickel-base alloy CM247LC is particularly sensitive for weld-cracking during powder-bed fusion, caused by an inappropriate laser spot diameter due to focus shifting. In this paper, the influence of a 4 mm shift on melt pool geometry, intensity, relative Archimedean density, crack microstructure and texture investigated, using two different calibration procedures system. The hot method procedure overcome thermally induced setting plane below build plane. After heating up operating temperature...
Abstract Background In Crohn’s disease (CD), artificial intelligence (AI) may improve treatment optimization and aid in clinical decision-making 1. The aim of the study is to compare results Bayesian Networks (BNs) both Expert Knowledge Model (EKM) Computer Algorithm Generated (CAGM) predicting corticosteroid-free remission at 52 weeks after introducing ustekinumab vedolizumab patients with CD. Methods Data were extracted from Dutch Initiative on Crohn Colitis (ICC) registry. Observations...
Purpose For geometries exhibiting overhanging surfaces, support structures are needed to dissipate process heat and minimize geometrical distortions attributed internal stresses. The use of is often time- cost-consuming. this reason, study aims propose an approach which minimizes the such structures. Design/methodology/approach minimizing structures, parameters in combination with a contour-like exposure strategy developed realize support-less less than 35°. These implemented shell-core...
Abstract Based on SLM parameters from previous works, which guarantee fully dense and crack free CM247LC samples, multi laser beam strategies have been pursued to reduce residual stresses or rather distortion during LPBF processing. By using a second post heating non-melting source with defocused lateral offset, cantilever is reduced more than 7.5%, compared the reference. pre-tests 9 different offset parameters, optimum has identified. Also, an upper limit for power of 65 W identified heat...
This study investigates the significance of melt pool temperature data obtained through pyrometry in a metal Laser Powder Bed Fusion (L-PBF, SLM) process. In an open-loop process like SLM, monitoring is key both determining quality and preparing towards closed-loop control. A two-color pyrometer integrated into laser beam path SLM machine, such that it collects emitted radiation from its vicinity. By this, with proper calibration, maximum surface can be in-situ as absolute value. Cuboidal...
This paper discusses the relevance of two-colour pyrometers' single channel signals for process monitoring laser powder bed fusion metal additive manufacturing. First, examples are presented where ratio temperature provided by pyrometer is misleading. Following a demonstration that such instances can be uncovered signals, an approach simplified signal analysis based on working principles provided. In closing, validation implemented, careful inspection and employment yielded suitable input...
This paper discusses the relevance of two-colour pyrometers' single channel signals for process monitoring laser powder bed fusion metal additive manufacturing. First, examples are presented where ratio temperature provided by pyrometer is misleading. Following a demonstration that such instances can be uncovered signals, an approach simplified signal analysis based on working principles provided. In closing, validation implemented, careful inspection and employment yielded suitable input...
Nickel-base alloys, such as "CM247LC", are usually used in the aviation field to manufacture high-pressure turbine blades with cooling channels, increase entry temperature and efficiency. Since there many different strategies for blades, requirements surface parameters (e.g. roughness) vary highly. In this study, five parameters, root mean square height, skewness, kurtosis, developed interfacial area ratio texture aspect modulated laser have been measured, analyzed, plotted diagrams compared...
Abstract High power parameters with increased scan velocities and beam diameters are investigated, to decrease the production time for crack sensitive alloy CM247LC. Results compared crack-free reference LPBF-samples in low range. The re-scaling approach high range is based on constant maximum laser intensity from While keeping velocity ratio constant, approach, also called “intensity approach”, provides an initial estimation spot size investigated cracks identified as “re-melting cracks”....
Abstract Compared to reference parameters in the low power and scan velocity range, which lead dense crack-free CM247LC LPBF samples due in-situ crack healing, high power, velocities increased laser beam diameters are investigated, decrease production time further. By keeping maximum intensity from ratio constant, approach provides an initial estimation for spot size regarding measured Archimedean density range. The investigated cracks identified as re-melting cracks. Solidification or hot...