Article
Materials Science, Multidisciplinary
Jiapeng Sun, Qisheng Sun, Ying Liu, Bangjun Li, Zheng Zhang, Bingqian Xu, Songsong Xu, Ying Han, Yanxin Qiao, Jing Han, Guosong Wu, Paul K. Chu
Summary: The study investigates the use of ultrasonic severe surface rolling (USSR) to enhance the corrosion resistance of SLM 316L stainless steel, and finds that the USSR processed samples exhibit significant improvement in corrosion resistance, attributed to the unique gradient structure and chemically homogeneous and high-quality surface.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Materials Science, Multidisciplinary
Zahra Abbasi, Hamid Reza Abedi
Summary: This study investigates the hot deformation behavior and recrystallization mechanisms of selective laser melted 316L stainless steel. The results show that the development of substructures and continuous recrystallization are the main softening mechanisms during thermomechanical processing. The presence of cellular substructures facilitates recrystallization, and both discontinuous and geometric dynamic recrystallization contribute to the deformation process.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Engineering, Manufacturing
Ying Liu, Jiapeng Sun, Yantao Fu, Bingqian Xu, Bangjun Li, Songsong Xu, Peilong Huang, Jianing Cheng, Ying Han, Jing Han, Guosong Wu
Summary: The gradient heterogeneous structure (GHS) architecture is proposed to achieve superior strength and ductility combination in additively manufactured (AM) 316L stainless steel. The GHS system consists of a gradient structured outer layer with varying grain size and a hierarchically heterostructured interlayer with varying length scales. By combining two types of heterogeneous structures, the GHS strengthens the synergistic effect, resulting in high-performance AM parts with superior strength and ductility.
ADDITIVE MANUFACTURING
(2021)
Article
Nanoscience & Nanotechnology
Jeong-Min Park, Yakai Zhao, Thomas Voisin, Dong-Hyun Lee, Shin-ichi Komazaki, Yoonseok Ko, Dong-Ik Kim, Jin-Yoo Suh, Heung Nam Han, Y. Morris Wang, Upadrasta Ramamurty, Jae-il Jang
Summary: The effect of hydrogen charging on the nanoindentation response of a selective laser melted 316L austenitic stainless steel was investigated. Results showed that the hardness increment due to hydrogen charging in SLM samples was relatively smaller compared to conventionally manufactured samples. The study also found that the charged SLM alloy had a lower hydrogen content and apparent hydrogen diffusivity, attributed to the ultrafine solidification cell structure in the SLM alloy. Additionally, the cell walls in the SLM alloy were relatively insensitive to hydrogen charging compared to the cell interiors.
SCRIPTA MATERIALIA
(2021)
Article
Chemistry, Physical
Feng Xu, Feiyu Xiong, Ming-Jian Li, Yanping Lian
Summary: This study presented a numerical model to investigate the grain growth mechanisms during selective laser melting. The simulation results were in good agreement with experimental data. The findings of this study are significant for optimizing process parameters and controlling the microstructure and mechanical properties of fabricated parts.
Article
Materials Science, Multidisciplinary
Hongqiao Qu, Jing Li, Fucai Zhang, Jiaming Bai
Summary: This study investigates the effects of solidification and remelting under a chessboard 67 degrees rotation scanning strategy on the microstructure and properties of selective laser melted 316L stainless steel. The findings provide insights into the relationship between microhardness, dislocation structure, and texture, contributing to a better understanding of the characteristics of 316L stainless steel.
MATERIALS & DESIGN
(2022)
Article
Engineering, Manufacturing
Yash Parikh, Mathew Kuttolamadom
Summary: The purpose of this research is to characterize and design property-graded bulk structures made from a single metallic alloy through a laser powder bed fusion process. The paper focuses on investigating the manufacture of stainless steel 316L structures and understanding the underlying causes of property variations within an acceptable range. The results show that property variations are influenced by porosity types/amounts, martensitic phase fractions, and grain sizes. This work lays the foundation for understanding and designing the mechanical performance of functionally-graded additively manufactured structures.
JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME
(2023)
Article
Engineering, Chemical
Dengzhi Yao, Ju Wang, Meng Li, Tingting Zhao, Yao Cai, Xizhong An, Ruiping Zou, Hao Zhang, Haitao Fu, Xiaohong Yang, Qingchuan Zou
Summary: This paper investigates the segregation of 316L stainless steel powders during spreading and identifies the segregation mechanisms using the discrete element method. The results show that particle size and distribution have an influence on segregation behavior and properties of the powder bed, and increasing blade velocity can weaken the segregation behavior.
Article
Engineering, Manufacturing
Karl Peter Davidson, Guy Littlefair, Sarat Singamneni
Summary: This research investigates the use of selective laser melting to convert duplex stainless steels into ferritic forms for better machinability, showing promising results through experimental machining evaluations. Comparisons of metallographic and micro-hardness assessments of laser melted and wrought specimens suggest that this approach can alleviate machinability problems in duplex stainless-steel systems.
MATERIALS AND MANUFACTURING PROCESSES
(2022)
Article
Engineering, Manufacturing
David J. Sprouster, W. Streit Cunningham, Gary P. Halada, Hanfei Yan, Ajith Pattammattel, Xiaojing Huang, Daniel Olds, Maryam Tilton, Yong S. Chu, Eric Dooryhee, Guha P. Manogharan, Jason R. Trelewicz
Summary: The hierarchical nature of additively manufactured materials requires a multimodal approach to quantify microstructural features and chemical heterogeneities. Using advanced synchrotron x-ray techniques and transmission electron microscopy, the analysis of microstructure and chemical heterogeneities in L-PBF 316L revealed significant dislocation density consistent with the formation of a cellular dislocation microstructure. The findings demonstrate the impact of microstructural defect state and its variation with printing speed on the resistance of L-PBF 316L to uniform and localized corrosion.
ADDITIVE MANUFACTURING
(2021)
Article
Materials Science, Multidisciplinary
Weihao Zhang, Honglin Ma, Qi Zhang, Shuqian Fan
Summary: The uniformity of a recoated powder layer directly affects the performance of parts manufactured by SLM, which is related to the characteristics of spatters. By using a coaxial optical path with enhanced optical transmittance, this study improved imaging of hot spatters in the SLM process.
MATERIALS & DESIGN
(2022)
Article
Engineering, Mechanical
Feng He, Chao Wang, Bin Han, Guma Yeli, Xin Lin, Zhijun Wang, Lilin Wang, Ji-jung Kai
Summary: The selective laser melted (SLM) 316L stainless steel (316L SS) has superior tensile ductility and doubled yield strength compared to its wrought counterpart. The improved yield strength is attributed to unique cellular substructures featured by Cr/Mo-segregation and trapped dislocations. The excellent ductility is mainly understood from deformation twinning and two newly discovered deformation mechanisms, deformation faulting and dislocation cell refinement, which dominate the whole tensile deformation significantly.
INTERNATIONAL JOURNAL OF PLASTICITY
(2022)
Article
Chemistry, Physical
Ricardo Santamaria, Mobin Salasi, William D. A. Rickard, Kod Pojtanabuntoeng, Garry Leadbeater, Mariano Iannuzzi, Steven M. Reddy, Md Zakaria Quadir
Summary: There is a growing interest in using selective laser melting (SLM) for metal additive manufacturing. However, our understanding of SLM-printed stainless steel is limited due to complex process variables. This study found discrepancies in crystallographic textures and microstructures compared to previous literature. The as-printed material showed macroscopic asymmetry in structure and crystallographic texture, with specific low-angle boundary features being identified as non-crystallographic.
Article
Construction & Building Technology
Giuseppe Brando, Francesca Romana Andreacola, Ilaria Capasso, Daniele Forni, Ezio Cadoni
Summary: This research investigates the strain rate effects on 17-4PH stainless steel produced by Selective Laser Melting (SLM) and evaluates its mechanical performance under dynamic conditions. The study uses advanced testing equipment to characterize the material behavior and explores the impact of printing direction and heat treatment. The results contribute to the understanding of the dynamic behavior of SLM-produced 17-4PH stainless steel, which has been rarely investigated before.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Sara Giganto, Susana Martinez-Pellitero, Joaquin Barreiro, Paola Leo, Ma Angeles Castro-Sastre
Summary: A significant correlation between scanning strategies and the quality of parts manufactured additively with Selective Laser Melting (SLM) technology is shown. The research evaluates the properties of 17-4PH parts manufactured using three usual scanning strategies (normal, concentric, and hexagonal). The hexagonal strategy is found to be the most appropriate in terms of porosity, while the normal strategy exhibits the best surface finish on the top face. The concentric strategy presents different results with larger and irregular pores, ductile tensile behavior, low roughness on lateral faces, and high geometrical errors with large scanning vectors.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Green & Sustainable Science & Technology
Simone Venettacci, Raffaello Cozzolino, Gennaro Salvatore Ponticelli, Stefano Guarino
Summary: This study compares an innovative thermal energy storage system with a traditional water-based system in terms of economic and environmental aspects in Italy. The innovative system has lower natural gas consumption and environmental impact, but higher cost compared to the traditional system.
SUSTAINABLE PRODUCTION AND CONSUMPTION
(2022)
Article
Engineering, Manufacturing
Gennaro Salvatore Ponticelli, Simone Venettacci, Oliviero Giannini, Stefano Guarino, Matthias Horn
Summary: This study focuses on optimizing the process parameters of 316L stainless steel components manufactured by Laser Powder Bed Fusion using fuzzy logic. A systematic experimental plan was conducted to determine the effects of volumetric energy density and building orientation on density, ultimate tensile strength, hardness, and roughness. A fuzzy model optimized through genetic algorithms was developed to identify the best process window for achieving optimal mechanical properties. The experimental results showed improved mechanical properties compared to traditional annealed 316L stainless steel, except for roughness. The fuzzy model demonstrated the ability to replicate experimental data with increasing precision, offering a new tool for understanding the relationship between input modifications, model precision, and process variability.
PROGRESS IN ADDITIVE MANUFACTURING
(2023)
Article
Chemistry, Physical
Simone Venettacci, Gennaro Salvatore Ponticelli, Flaviana Tagliaferri, Stefano Guarino
Summary: This work provides an economic and environmental analysis for a biocide-free antifouling coating that reduces fuel consumption, CO2 emissions, and overall environmental impacts in marine applications. The study shows that the coating leads to a 8.8% reduction in costs compared to conventional paint, with a 13,700 kg/y (9.6%) decrease in annual fuel consumption and a 43.3 ton/y reduction in CO2 emissions. It also lowers the overall environmental impacts by nearly 10%. Overall, the innovative coating promotes greater environmental sustainability for the yacht's service life.
Article
Chemistry, Multidisciplinary
Gennaro Salvatore Ponticelli, Marianna Gallo, Ilaria Cacciotti, Oliviero Giannini, Stefano Guarino, Andrea Budelli, Roberto Nigro
Summary: Modelling and predicting the kinetics of microbial growth and metabolite production during fermentation is important for the development of functional probiotics foods on large scale production. Various mathematical models have been proposed to predict bacterial growth rate, but they can only replicate the exponential phase and rely on empirical data for accurate estimation of kinetic parameters. Genetic algorithms offer a promising solution for modelling dynamic biological systems. This study aims to propose a genetic algorithm for modelling and predicting bacterial growth of Lactobacillus paracasei CBA L74 strain fermented on rice flour substrate. Experimental results show that pH control has less influence on bacterial growth compared to lactic acid, and the genetic algorithm allowed the definition of an optimal empirical model that extends predictive capability to stationary and lag phases.
APPLIED SCIENCES-BASEL
(2023)
Article
Materials Science, Characterization & Testing
Mario Di Siena, Silvio Genna, Patrizia Moretti, Gennaro Salvatore Ponticelli, Simone Venettacci, Pietro Russo
Summary: This study experimentally analyzed the effects of laser radiation on semi-crystalline polyethylene-based polymers. The aim was to develop a foundation for the future development of an innovative joining system using laser technology. Multiple process monitoring techniques were used to evaluate the thermo-mechanical properties of the tested materials, in order to identify the optimal parameters for laser joining operations. The results are important for avoiding ineffective heating or excessive degradation of the material.
Article
Automation & Control Systems
Gennaro Salvatore Ponticelli, Simone Venettacci, Flaviana Tagliaferri, Stefano Guarino
Summary: This study proposes the use of 3D printing technology to fabricate carbon reinforced polyether ether ketone (PEEK) supports for replacing conventional aluminium brackets in commercial aircraft overhead lockers. The economic assessment reveals the benefits of using 3D printing in terms of fuel consumption reduction and weight reduction, leading to economic savings. The environmental analysis shows that this innovative strategy can reduce CO2 emissions and promote sustainability in the aviation industry.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2023)
Article
Engineering, Manufacturing
Gianluca Rubino, Simone Venettacci
Summary: The paper describes an innovative coating process for complex-geometry components, using polymer powder fluidized bed technology and an adhesive silicone primer. The study validates the proposed technical solution by comparing it with the traditional electrostatic coating process. Results show that the innovative deposition system achieves a homogeneous coating with a thickness of -15-20 μm, compared to -25-90 μm for the traditional process. The proposed technique also ensures coating uniformity, protective coverage, and coloring, with lower consumption of coating powder.
JOURNAL OF MANUFACTURING PROCESSES
(2023)
Proceedings Paper
Engineering, Biomedical
Ponticelli Gennaro Salvatore, Venettacci Simone, Tagliaferri Flaviana, Trovalusci Federica, Genna Silvio, Guarino Stefano
Summary: The study aims to investigate the capability of a nanosecond pulsed fiber laser to machine yttria-stabilized zirconia samples and identify the most suitable process operational parameters combinations that ensure specific surface topographies while minimizing the machining time. The results show that laser milling is a highly repeatable, accurate, and time-saving process for dental restorations made of zirconia-based biomaterials.
V CIRP CONFERENCE ON BIOMANUFACTURING
(2022)
