Article
Engineering, Manufacturing
William L. Smith, John D. Roehling, Maria Strantza, Rishi K. Ganeriwala, Ava S. Ashby, Bey Vrancken, Bjorn Clausen, Gabriel M. Guss, Donald W. Brown, Joseph T. McKeown, Michael R. Hill, Manyalibo J. Matthews
Summary: The study successfully reduced residual stress in laser powder bed fusion process using in situ annealing, with noticeable stress reduction on various planes of stainless steel parts. Experimental results were in excellent agreement with numerical simulations, indicating potential for further optimization to reduce processing time.
ADDITIVE MANUFACTURING
(2021)
Article
Optics
M. J. Javidi, S. M. Hosseini, F. Khodabakhshi, M. Mohammadi, L. Orovcik, V. Nagy Trembosova, S. Nagy, M. Nosko
Summary: This study investigates the mechanical properties and microstructure of additively manufactured 316L stainless steels reinforced with Al2O3 nanoparticles. Optimal laser power, scan speed, hatch space, and layer thickness were determined using Taguchi analysis. The energy density was found to be critical in controlling the integrity and cracking behavior of the structures. Characterization of the microstructure and mechanical properties revealed refined grain structure and improved hardness due to the incorporation and uniform distribution of alumina nanoparticles. These nanoparticles directly strengthened the stainless steel matrix and influenced the solidification mechanisms and microstructural features.
OPTICS AND LASER TECHNOLOGY
(2023)
Article
Engineering, Manufacturing
Tao Liu, Cody S. Lough, Hossein Sehhat, Yi Ming Ren, Panagiotis D. Christofides, Edward C. Kinzel, Ming C. Leu
Summary: This paper investigates the in-situ characterization of the powder layer using thermographic inspection and proposes a method to predict part distortion and prevent damage to the recoater system and powder layer abrasion.
ADDITIVE MANUFACTURING
(2022)
Article
Engineering, Manufacturing
Paul Sandmann, Soren Keller, Nikolai Kashaev, Shaaz Ghouse, Paul A. Hooper, Benjamin Klusemann, Catrin M. Davies
Summary: This study demonstrates that laser shock peening (LSP) technology can effectively improve the residual stress state of components manufactured by laser powder bed fusion (LPBF), while traditional heat treatments may not completely eliminate these detrimental stresses. Experimental results show that LSP can convert the surface tensile stresses of LPBF components into beneficial compressive residual stresses.
ADDITIVE MANUFACTURING
(2022)
Article
Materials Science, Multidisciplinary
X. X. Zhang, H. Andrae, S. Harjo, W. Gong, T. Kawasaki, A. Lutz, M. Lahres
Summary: In-situ neutron diffraction was used to investigate the residual strains, stresses, and dislocation density in LPBF AlSi10Mg during loading-unloading-reloading deformation. The study revealed that the AlSi10Mg alloy exhibits notable dislocation annihilation phenomenon in the Al matrix during unloading stages, driven by compressive residual stresses.
MATERIALS & DESIGN
(2021)
Article
Mechanics
Foued Abroug, Axel Monnier, Lionel Arnaud, Yannick Balcaen, Olivier Dalverny
Summary: This paper investigates the high cycle fatigue behavior of 316L stainless steel parts obtained through rolling or LPBF additive manufacturing. The study compares the fatigue strength of additively produced parts with that of raw rolled products. The results show that laser welding does not degrade the fatigue strength of additively produced parts. Additionally, the study finds that additively produced parts are more sensitive to the presence of defects compared to rolled parts.
ENGINEERING FRACTURE MECHANICS
(2022)
Review
Instruments & Instrumentation
Cecilia Rossi, Francesco Buatier de Mongeot, Giulio Ferrando, Giacomo Manzato, Mickael Meyer, Luigi Parodi, Stefano Sgobba, Marco Sortino, Emanuele Vaglio
Summary: Nowadays, Additive Manufacturing (AM) has gained popularity and is being used in various fields, including high energy physics. This paper aims to compare traditional and 3D printed stainless steel AISI 316L products in the specific high energy applications environment. Experimental tests are conducted on the manufactured samples to analyze their material composition and assess properties such as mechanical performance in cryogenic application, high magnetic fields, and ultra-vacuum compatibility. The analysis of material behavior allows the strengths and weaknesses of the technology to be identified compared to traditional AISI 316L.
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
(2023)
Article
Materials Science, Multidisciplinary
Maximilian Sprengel, Gunther Mohr, Simon J. Altenburg, Alexander Evans, Itziar Serrano-Munoz, Arne Kromm, Thilo Pirling, Giovanni Bruno, Thomas Kannengiesser
Summary: This study focuses on the distribution of bulk triaxial RS and surface RS in LPBF austenitic steel 316L. It highlights the benefit of using multiple RS determination methods and in situ thermography monitoring to characterize the RS in LPBF processed parts.
ADVANCED ENGINEERING MATERIALS
(2022)
Article
Engineering, Mechanical
Daniel Kotzem, Stefan Kleszczynski, Felix Stern, Arno Elspass, Jochen Tenkamp, Gerd Witt, Frank Walther
Summary: The study found that the metal laser powder bed fusion process is highly tolerant to defects, with 0.3 mm defects not initiating cracks, while defects of 1.0-1.5 mm clearly led to crack initiation and propagation.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Materials Science, Multidisciplinary
L. Lemarquis, P. F. Giroux, H. Maskrot, B. Barkia, O. Hercher, P. Castany
Summary: The study found that the microstructure of 316L produced by LPBF technology undergoes different levels of grain refinement and texture changes after cold-rolling, depending on the initial microstructure. Mechanical twinning was also observed in both microstructures, with a twinned surface ratio exceeding 30%.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2021)
Article
Chemistry, Physical
Luis H. Olivas-Alanis, Antonio Abraham Fraga-Martinez, Erika Garcia-Lopez, Omar Lopez-Botello, Elisa Vazquez-Lepe, Enrique Cuan-Urquizo, Ciro A. Rodriguez
Summary: The development of additive manufacturing processes has allowed for the production of complex and smart structures. This study investigated the mechanical behavior of different lattice structures through experimental and computational methods. The results highlighted the significant impact of cell shape, size, and orientation on the mechanical properties of the materials.
Article
Engineering, Manufacturing
P. Mohammadpour, H. Yuan, A. B. Phillion
Summary: This study combines optical and electron microscopy techniques with thermodynamic simulations to evaluate the solidification performance and precipitate formation in Inconel625 LPBF microstructure. Experimental and computational methods are used to determine the level of microsegregation and patterns, as well as the identification of precipitates embedded in the interdendritic regions.
ADDITIVE MANUFACTURING
(2022)
Article
Nanoscience & Nanotechnology
Lei Tang, Oxana Magdysyuk, Fuqing Jiang, Yiqiang Wang, Alexander Evans, Saurabh Kabra, Biao Cai
Summary: This study reveals the mechanical and microstructural responses of a 316L ASS at low temperatures using in situ neutron diffraction tensile tests. The results show a linear decrease in stacking fault energy with temperature, leading to a transition in deformation mechanism.
SCRIPTA MATERIALIA
(2022)
Article
Engineering, Manufacturing
Jiong Zhang, Hao Wang
Summary: This study develops a magnetically driven internal finishing method to improve the surface quality of components fabricated through laser powder bed fusion. The results demonstrate significant improvement in surface roughness compared to traditional methods, making it a more efficient alternative.
JOURNAL OF MANUFACTURING PROCESSES
(2022)
Article
Chemistry, Physical
Alexey Fedorenko, Boris Fedulov, Yulia Kuzminova, Stanislav Evlashin, Oleg Staroverov, Mikhail Tretyakov, Evgeny Lomakin, Iskander Akhatov
Summary: The study found that 316L stainless steel tensile specimens manufactured using the LPBF process exhibit anisotropy, with vertically built specimens showing significantly lower mechanical properties than horizontally built specimens. This difference may be explained by the influence of residual stress on the mechanical behavior.
Article
Materials Science, Multidisciplinary
Itziar Serrano-Munoz, Alexander Evans, Tatiana Mishurova, Maximilian Sprengel, Thilo Pirling, Arne Kromm, Giovanni Bruno
Summary: The residual stress in laser powder bed fusion (LPBF) IN718 alloy samples produced using a 67 degrees-rotation scan strategy was investigated via laboratory X-ray diffraction (XRD) and neutron diffraction (ND), showing significant non-uniformity and difficulty in accurate determination through the stress balance method.
ADVANCED ENGINEERING MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Tobias Fritsch, Lena Farahbod-Sternahl, Itziar Serrano-Munoz, Fabien Leonard, Christoph Haberland, Giovanni Bruno
Summary: This research investigates cylindrical struts fabricated by L-PBF using X-ray computed tomography (XCT) to explore the dependence of different defects on the build angle. The study proposes innovative analysis methods to correlate shape and position of pores, determine angular-resolved surface roughness, and quantify the amount of re-entrant surface features.
ADVANCED ENGINEERING MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Maximilian Sprengel, Gunther Mohr, Simon J. Altenburg, Alexander Evans, Itziar Serrano-Munoz, Arne Kromm, Thilo Pirling, Giovanni Bruno, Thomas Kannengiesser
Summary: This study focuses on the distribution of bulk triaxial RS and surface RS in LPBF austenitic steel 316L. It highlights the benefit of using multiple RS determination methods and in situ thermography monitoring to characterize the RS in LPBF processed parts.
ADVANCED ENGINEERING MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Simon Oster, Tobias Fritsch, Alexander Ulbricht, Gunther Mohr, Giovanni Bruno, Christiane Maierhofer, Simon J. Altenburg
Summary: The detection of internal irregularities is crucial for quality assessment in metal-based additive manufacturing. In this study, the registration of thermal imaging and X-ray micro computed tomography datasets is carried out for the development of a porosity prediction model. A novel preprocessing methodology is introduced to deal with the challenging deformations caused by shrinkage and material elevation effects.
Article
Chemistry, Multidisciplinary
Alexander Heldmann, Michael Hofmann, Markus Hoelzel
Summary: The software DISEMM is designed to analyze diffraction data from in situ loading experiments on polycrystalline samples to determine single-crystal elastic constants (SECs) and perform elasto-plastic self-consistent (EPSC) modeling of lattice strains. The software can obtain SECs from powder-diffraction elastic constants using various grain-to-grain interaction models and consider the texture of the polycrystalline sample. It also calculates the stress transfer between phases in two-phase materials and its impact on the apparent elastic properties.
JOURNAL OF APPLIED CRYSTALLOGRAPHY
(2022)
Editorial Material
Materials Science, Multidisciplinary
Giovanni Bruno, Christiane Maierhofer
Article
Imaging Science & Photographic Technology
Athanasios Tsamos, Sergei Evsevleev, Rita Fioresi, Francesco Faglioni, Giovanni Bruno
Summary: The greatest challenge in using DCNNs for automatic segmentation of microstructural XCT data is the acquisition of sufficient and relevant training data. This study introduces a method for generating synthetic XCT data for a challenging composite material. The proposed method achieves successful segmentations by using data augmentation, a special deep convolutional neural network, and a multi-view forwarding strategy. An overall Dice score of 0.77 is obtained. The methods presented in this work are applicable to other materials and imaging techniques. Successful segmentation with synthetic data can accelerate scientific output.
JOURNAL OF IMAGING
(2023)
Article
Chemistry, Physical
Lorenleyn de la Hoz Alford, Camila Gomes Pecanha de Souza, Sidnei Paciornik, Jose Roberto M. d'Almeida, Brenno Santos Leite, Harold C. Avila, Fabien Leonard, Giovanni Bruno
Summary: Two biopolyol-based foams derived from banana leaves or stems were characterized for their compression mechanical behavior and 3D microstructure. They developed a methodology of image acquisition, processing, and analysis to discriminate the foam cells and measure their numbers, volumes, and shapes. The compression behaviors of the two foams were similar, but the average cell volume was larger for the foam derived from stems. The number of cells increased with compression while the average cell volume decreased. Cell shapes did not change with compression, suggesting the possibility of cell collapse. This study provides insights into the potential use of biopolyol-based foams as green alternatives to petrol-based foams.
Article
Materials Science, Multidisciplinary
Anna-Lena Otte, Phuong Thao Mai, Andreas Stark, Markus Hoelzel, Michael Hofmann, Jens Gibmeier
Summary: The aerospace alloy Ti-6246 was subjected to inductive heat treatments to study the emerging phases at any point of the process. The samples were prepared by homogenization treatment and quenching to trigger α-martensite formation. The microstructure stability and martensite decomposition path were characterized and analyzed.
Article
Chemistry, Inorganic & Nuclear
Sebastian Benz, Da Chen, Andreas Moeller, Michael Hofmann, David Schnieders, Richard Dronskowski
Summary: Carbonic acid, a key molecule in biochemistry, geochemistry, and extraterrestrial chemistry, has been studied for its crystal structure which shows strong hydrogen bonding, pi bonding, and influence of crystal field.
Article
Imaging Science & Photographic Technology
Deepak Mani, Andreas Kupsch, Bernd R. Mueller, Giovanni Bruno
Summary: This study evaluates images obtained using diffraction enhanced imaging (DEI) technique and compares the effectiveness of different fitting functions for typical rocking curves (RCs). A robust algorithm is developed to extract meaningful information from each pixel of the image. The potential of the algorithm is demonstrated with two specimens.
JOURNAL OF IMAGING
(2022)
Article
Engineering, Manufacturing
Tim Richter, Marcel Giese, Michael Rhode, Dirk Schroepfer, Thomas Michael, Tobias Fritsch
Summary: Multi-element systems with defined entropy, such as high entropy alloys (HEA) and medium entropy alloys (MEA), are important material concepts in materials research. While the synthesis, microstructures, and properties of these alloys have been extensively studied, their weldability has been largely neglected. In this study, the weldability of CoCrFeMnNi HEA and CoCrNi MEA for TIG welding is investigated, with a focus on the influence of surface preparation. The results show distinct formation of cracks in the heat affected zone (HAZ), but the exact crack mechanism remains unclear.
JOURNAL OF MANUFACTURING AND MATERIALS PROCESSING
(2022)
Article
Instruments & Instrumentation
Simon J. Altenburg, Anne Strasse, Andrey Gumenyuk, Christiane Maierhofer
Summary: Additive manufacturing offers novel applications, but the complex manufacturing process and production of defect-free, reliable, and durable parts remain a challenge. Thermography is a valuable tool for process surveillance in metal additive manufacturing, particularly in high-temperature environments where cameras operating in the visible spectral range can be used.
QUANTITATIVE INFRARED THERMOGRAPHY JOURNAL
(2022)