Article
Engineering, Chemical
Daniel Oropeza, Ryan W. Penny, Daniel Gilbert, A. John Hart
Summary: This study demonstrates the use of a precision, mechanized powder spreading testbed coupled with transmission x-ray imaging for spatially-resolved, non-contact powder layer density measurements. The influence of several variables on the spreading of aluminum oxide powders is studied, including powder size and shape, spreading tool choice, traverse speed, and powder dispensing methodology. The findings show that these factors have an impact on the layer density of the spread powder.
Article
Chemistry, Physical
Nicholas Derimow, Justin M. Gorham, May L. Martin, Jake T. Benzing, Ryan M. White, Nikolas Hrabe
Summary: XPS and SEM/TEM analysis were conducted on Ti-6Al-4V powders with different oxygen contents to investigate the effects of reuse on powder characteristics. The results showed a decrease in TiO2 and an increase in Al2O3 on the surface of reused powders, which is consistent with thermodynamics. Additionally, a higher amount of nitrogen and nitride was found on the surface of Grade 23 powders as a function of reuse.
APPLIED SURFACE SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
V. B. Vukkum, Furkan Ozdemir, Steven Storck, R. K. Gupta
Summary: This study investigates the influence of additives on the microstructure and corrosion performance of 316 L stainless steel using modified feedstock and laser-powder bed fusion technique.
Article
Materials Science, Multidisciplinary
A. Ardeshiri Lordejani, D. Colzani, M. Guagliano, S. Bagherifard
Summary: This research compared multiple finite element modeling approaches to analyze the impact of powder features on deposit properties. By introducing a complex algorithm, the influence of parameters such as particle size, shape, oxidation extent, and impact angle on deposition indicators was accurately evaluated. The results confirmed the effectiveness of the proposed numerical framework in tuning deposit properties.
MATERIALS & DESIGN
(2022)
Article
Engineering, Manufacturing
Jaime Berez, Christopher Saldana
Summary: This study investigated how stainless steel powder feedstocks are affected by prior LPBF processes and how these effects impact subsequent builds. It was found that powder characteristics evolve with exposure to LPBF processes, particularly in terms of powder size distribution and bulk flow, but have no significant effects on tensile properties. The reliability modeling methods proved to be effective tools for modeling fatigue variability in LPBF manufactured components, showing that fatigue life remains invariant with changes in powder condition.
JOURNAL OF MANUFACTURING PROCESSES
(2021)
Article
Engineering, Manufacturing
Rui Xu, Wenguang Nan
Summary: The spreadability of powder in additive manufacturing plays a crucial role in determining the quality of the final product. This study examines the metrics of spreadability for powders of different sizes and analyzes the factors that affect spreadability, including cohesion and interlocking between particles. The results show that comparing relative powder spreadability should consider the ratio of gap height to particle size. The study also proposes a physical model to predict the maximum fraction of spread layer at a specified gap height.
ADDITIVE MANUFACTURING
(2023)
Article
Green & Sustainable Science & Technology
J. Joju, D. Verdi, W. S. Han, L. Y. Hang, N. Soh, C. C. Hampo, N. Liu, S. S. Yang
Summary: This study conducted a sustainability assessment on the reuse of un-melted feedstock powder in Directed Laser Deposition. The results showed that the un-melted powder experienced minimal changes and the Life Cycle Assessment demonstrated significant environmental benefits from reusing the powder. Reusing the powder resulted in a 15%-25% reduction in environmental impact compared to using only virgin material.
JOURNAL OF CLEANER PRODUCTION
(2023)
Article
Engineering, Mechanical
Thomas Childerhouse, Everth Hernandez-Nava, Nikolaos Tapoglou, Rachid M'Saoubi, Luiz Franca, Wayne Leahy, Martin Jackson
Summary: This study found that removing defects during machining can significantly improve fatigue performance in metal additive manufactured components, while hot isostatic pressing treatment can effectively reduce gas porosity to a lesser degree than machining.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Materials Science, Multidisciplinary
Simon Cholewa, Lucas Stieglitz, Andreas Jaksch, Bernhard Rieger, Dietmar Drummer
Summary: Current research on laser-based powder bed fusion of polymers (PBF-LB/P) is mainly focused on the relationship between process and component properties of commercially available powder materials, limiting its application scope. This study proposes an innovative approach by synthesizing a tailored polypropylene for PBF-LB/P, and evaluating its performance in the process. Syndiotactic polypropylene with advantageous properties was synthesized and directly used as feedstock for PBF-LB/P. The obtained polymer was analyzed for its properties and the processability of the material system was demonstrated.
ACS APPLIED POLYMER MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Naveen Karuthodi Mohandas, Alex Giorgini, Matteo Vanazzi, Ton Riemslag, Sean Paul Scott, Vera Popovich
Summary: This study investigated the gaseous hydrogen embrittlement behavior of additively manufactured (AM) Inconel 718 produced from sustainable feedstock. The results showed that all Inconel 718 samples, including AM-as-processed, AM-heat-treated, and conventional samples, exhibited severe hydrogen embrittlement. Moreover, the heat-treated AM Inconel 718 demonstrated a 64% lower degree of hydrogen embrittlement compared to the wrought counterpart. This was attributed to the anisotropic microstructure induced by the AM process.
Review
Materials Science, Composites
Soyeon Park, Kun (Kelvin) Fu
Summary: Fused deposition modeling (FDM) is a manufacturing method based on polymer melting and extrusion, which has attracted attention in various fields. Understanding the properties and behavior of polymer systems is crucial for using polymer composite materials in manufacturing and printing, and plays a key role in advancing additive manufacturing.
COMPOSITES SCIENCE AND TECHNOLOGY
(2021)
Article
Nanoscience & Nanotechnology
D. W. Wang, Y. H. Zhou, X. Y. Yao, Y. P. Dong, S. H. Feng, Z. Y. Liu, H. Wang, M. Yan
Summary: This study explores the inheritance relationship between the feedstock powder and the as-printed products in laser powder bed fusion. A core-shell powder structure is generated through ball milling modification, leading to significant grain refinement and improved mechanical performance. The printed samples show different microstructure transformations depending on the type of feedstock powder used, highlighting the importance of tailoring the feedstock powder for developing high-performance materials in additive manufacturing.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Engineering, Manufacturing
Ilaria Baesso, David Karl, Andrea Spitzer, Aleksander Gurlo, Jens Guenster, Andrea Zocca
Summary: The study compared the flow behavior of powders using different methods, with ASTM B329 measurement of bulk density showing the best correlation with powder bed density. Advanced methods like rotating drum and powder rheometry did not demonstrate strong correlations, but provided additional information for evaluating the dynamic behavior of powders.
ADDITIVE MANUFACTURING
(2021)
Review
Engineering, Manufacturing
Zahra Lotfizarei, Amir Mostafapour, Ahmed Barari, Alireza Jalili, Albert E. Patterson
Summary: Material extrusion additive manufacturing (MEAM) is a common process for building solid geometry using selective extrusion of molten material. One emerging process within this group is powder material extrusion (PME), which extrudes feedstock consisting of metal or ceramic powder suspended in a thermoplastic matrix. PME offers low cost, simple equipment, and lack of industrial hazards and residual stresses.
ADDITIVE MANUFACTURING
(2023)
Article
Engineering, Chemical
Hamid Salehi, John Cummins, Enrico Gallino, Vivek Garg, Tong Deng, Ali Hassanpour, Mike Bradley
Summary: Powder bed fusion (PBF), a type of additive manufacturing, has great potential in producing fully functional objects with high densities. The quality of the powder bed, known as powder spreading, plays a crucial role in determining the final quality of the produced object. This study used a new testing apparatus to analyze the impact of various factors, such as the shape of the recoater, the gap size, and powder flow properties, on the packing fraction of the powder bed. The results demonstrated that all the variables examined influenced the packing fraction and the size and shape variations across the build plate.
Article
Engineering, Mechanical
Ankita Mangal, Elizabeth A. Holm
INTERNATIONAL JOURNAL OF PLASTICITY
(2019)
Article
Materials Science, Multidisciplinary
Toby Francis, Ian Chesser, Saransh Singh, Elizabeth A. Holm, Marc De Graef
Article
Materials Science, Multidisciplinary
Brian L. DeCost, Bo Lei, Toby Francis, Elizabeth A. Holm
MICROSCOPY AND MICROANALYSIS
(2019)
Editorial Material
Multidisciplinary Sciences
Elizabeth A. Holm
Article
Materials Science, Multidisciplinary
Ian Chesser, Elizabeth A. Holm, Michael J. Demkowicz
Article
Materials Science, Multidisciplinary
I Chesser, T. Francis, M. De Graef, E. A. Holm
Article
Materials Science, Multidisciplinary
Elizabeth A. Holm, Ryan Cohn, Nan Gao, Andrew R. Kitahara, Thomas P. Matson, Bo Lei, Srujana Rao Yarasi
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2020)
Article
Materials Science, Multidisciplinary
Tim Hsu, William K. Epting, Hokon Kim, Harry W. Abernathy, Gregory A. Hackett, Anthony D. Rollett, Paul A. Salvador, Elizabeth A. Holm
Summary: By utilizing a generative adversarial network (GAN) framework to learn and generate 3D microstructures of solid oxide fuel cell electrodes, the results show that the generated microstructures closely match the original ones and exhibit similar performance in electrochemical simulations.
Correction
Materials Science, Multidisciplinary
I. Chesser, T. Francis, M. De Graef, E. A. Holm
Article
Multidisciplinary Sciences
Ali Riza Durmaz, Martin Mueller, Bo Lei, Akhil Thomas, Dominik Britz, Elizabeth A. Holm, Chris Eberl, Frank Mucklich, Peter Gumbsch
Summary: The authors use deep learning for segmentation of complex phase steel microstructures, improving analysis capabilities and providing a new method for materials research and development. Through image processing and training, accurate inference of microstructure properties can be achieved.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Zongrui Pei, Kyle A. Rozman, Omer N. Dogan, Youhai Wen, Nan Gao, Elizabeth A. Holm, Jeffrey A. Hawk, David E. Alman, Michael C. Gao
Summary: With the emergence of new alloys like high-entropy alloys, the traditional trial-and-error method faces challenges in alloy design; assisted by machine-learning method, microstructure images can be identified and a new neural network method proposed for inverse alloy design; this work lays the foundation for inverse alloy design based on microstructure images.
Article
Materials Science, Multidisciplinary
Mohammad Abdulsalam, Nan Gao, Bryan A. Webler, Elizabeth A. Holm
Summary: This study utilized SEM/EDS analysis output to predict inclusion types in steel, using Random Forest and convolutional neural networks for model comparison. CNN showed better accuracy in binary (92%) and 4-class (78%) models compared to RF (binary 87%, 4-class 75%). Results for the 5-class model were similar, with 60% accuracy for RF and 59% for CNN.
FRONTIERS IN MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Elizabeth A. Holm, Ryan Cohn, Nan Gao, Andrew R. Kitahara, Bo Lei, Srujana Rao Yarasi, Thomas P. Matson
ADVANCED MATERIALS & PROCESSES
(2021)
Article
Chemistry, Multidisciplinary
Qixiang Luo, Elizabeth A. Holm, Chen Wang
Summary: The extensive use of carbon nanomaterials in industrial settings has raised concerns over potential health risks of occupational exposure. Airborne carbonaceous nanomaterials often form complex structures, making manual classification difficult. A CNN-based machine learning method achieved high accuracy in automatically detecting and classifying complex carbon nanostructures, showing potential for application in other nanomaterials.
NANOSCALE ADVANCES
(2021)
Article
Materials Science, Multidisciplinary
Shuai Zhang, Shuye Zhang, Hongzhi Zhou, Kyung-Wook Paik, Tianran Ding, Weimin Long, Sujuan Zhong, Peng He
Summary: Microwave Hybrid Heating (MHH) is a promising method for material joining, allowing for selective and uniform heating. This experimental study focused on investigating the characteristics and reliability of joints made using nano-Sn-3.0Ag-0.5Cu soldering paste and MHH technique. The research findings showed that the shear strength of the joints reached its peak value under specific microwave power and exposure time, but decreased after thermal shock tests.
MATERIALS CHARACTERIZATION
(2024)
Article
Materials Science, Multidisciplinary
Peibin Ma, Mingyang Wang, Aiying Chen, Lijian Gu, Zhiyi Ding, Xiaogui Wang, Bin Gan
Summary: Nano-twinned boundaries in high-temperature alloys play a crucial role in regulating the distribution of nano-precipitates and enhancing mechanical properties.
MATERIALS CHARACTERIZATION
(2024)
Article
Materials Science, Multidisciplinary
Jiachen Zhang, Fan Lu, Xinxin Liu, Taiwen Huang, Rui Li, Changsheng Tan, Guojun Zhang, Lin Liu
Summary: This study investigates the effects of Re and Ta interactions on the precipitation of the TCP phase in experimental alloys under long-term thermal exposure. The study finds that microstructure segregation is not fully eliminated even with standard heat treatment, and the interaction between Re and Ta enhances the formation of the TCP phase. Thermodynamic calculations and first-principles analysis reveal that Re significantly improves the driving force of TCP phase precipitation. The study also observes a phase transition from the sigma-phase to the P-phase, with Ni playing a crucial role in the diffusion process.
MATERIALS CHARACTERIZATION
(2024)
Article
Materials Science, Multidisciplinary
Ronit Roy, Adil Shaik, Matthew Topping, Fei Long, Mark R. Daymond
Summary: This study demonstrates the improvements in characterizing localized dislocation distribution using the HR-EBSD method compared to the conventional approach. Two extreme examples of deformation conditions were investigated to show the efficacy of HR-EBSD in identifying dislocations and subtle features. The direct correlation between slip bands and HR-EBSD estimated GNDs is also presented, enhancing the scope of this approach in identifying individual slip bands.
MATERIALS CHARACTERIZATION
(2024)
Article
Materials Science, Multidisciplinary
Wenshan Guo, Hui Zhang, Qingjun Zhou, Guangchun Xiao, Ning Guo, Wei Zhao, Gang Wang
Summary: The microstructures and corrosion resistance of TC11 components were significantly improved using a high-power, high-speed laser metal deposition (LMD) process and subsequent post-heat treatment, with greater improvements observed in the deposition direction. The significant improvement of corrosion resistance in the deposition direction is mainly due to the weakening of the charged galvanic corrosion effect between the non-interlayer zone and interlayer zone.
MATERIALS CHARACTERIZATION
(2024)
Article
Materials Science, Multidisciplinary
Shuai Xu, Rui Cao, Junheng Gao, Yu Zhang, Haitao Zhao, Shuize Wang, Yuhe Huang, Guilin Wu, Honghui Wu, Chaolei Zhang, Xinping Mao
Summary: In this study, the microstructures and mechanical properties of interphase precipitation strengthening micro-alloyed steels were investigated. The addition of Cr was found to increase the yield strength without significant decrease of ductility. Thermodynamics analysis revealed that the addition of Cr led to grain refinement and decrease of sheet spacing of nanoprecipitates. Calculations showed that the decrease of interphase-precipitated carbides sheet spacing and the refinement of grain size were responsible for the strength enhancement of Cr microalloyed steel.
MATERIALS CHARACTERIZATION
(2024)
Article
Materials Science, Multidisciplinary
Zhaoxin Zhong, Biao Zhang, Yuhan Ren, Jian Ye, Jiawei Zhang, Feng Ye
Summary: In this study, bioinspired web-liked multiphase composites were successfully constructed using boron-modified polysilazane polymer. The composites consisted of long TiB nanowires as 'web' and hybrid TiC and Ti3Si particles as 'nodes'. The enhanced strength of these composites was attributed to the synergistic load transfer of the hybrid reinforcements. This study provides a promising design approach for developing high-performance composites with high reinforcement content, utilizing polymer instead of traditional ceramic powder.
MATERIALS CHARACTERIZATION
(2024)
Article
Materials Science, Multidisciplinary
Geng Liu, Linran Yu, Jie Su, Ran Ding, Min Xiong, Qi Gao
Summary: In this study, a flash austenitization heat treatment approach was used to achieve a dual-phase microstructure consisting of retained austenite and fine-grained ferrite in low-carbon TRIP steel. Phase-field simulations revealed the acceleration of ferrite transition kinetics in the Mn-depleted region and the influence of chemical heterogeneity of C and Mn on the stabilization of austenite.
MATERIALS CHARACTERIZATION
(2024)
Article
Materials Science, Multidisciplinary
Zhichao Yang, Dehui Zheng, Zhen Wang, Tingbin Liang, Shuangbao Wang
Summary: In this study, the configurations, formation process, and properties of the Cu-rich layer formed during TJE of Al alloys were revealed using aberration-corrected scanning TEM (STEM), STEM image simulations, and first-principles calculations. The results showed a new orientation relationship between the Cu-rich layer and Al matrix, and provided insights into the formation mechanisms of the Cu-rich layer and Cu diffusion zone.
MATERIALS CHARACTERIZATION
(2024)
Article
Materials Science, Multidisciplinary
Shuai Chen, Ruyu Tian, Jiayue Wen, Yanhong Tian
Summary: In this study, the interfacial microstructure evolution and reliability of Cu/Sn-3.0Ag-0.5Cu (SAC305)/Ni and Cu/Sn-3.0Ag-0.5Cu-0.05TiO2 (SAC305-0.05TiO2)/Ni interconnections under thermal shock were investigated. The results showed that the addition of TiO2 nanoparticles can suppress the growth of interfacial IMCs and improve the reliability of the connections.
MATERIALS CHARACTERIZATION
(2024)
Article
Materials Science, Multidisciplinary
Yunbin Lu, Yangju Feng, Wei Wang, Wenke Wang, Jianlei Yang, Wenzhen Chen, Guorong Cui, Dongdong Zhuang, Hongyang Cao
Summary: In order to improve the wear resistance of titanium alloy, titanium matrix composites with network distributed TiBw were fabricated. The results showed that the wear rate of the composites decreased by 17.2% at room temperature and 38.4% at high temperature compared to the TA15 alloy. The TiBw in the composites enhanced work hardening, improved thermal conductivity, and effectively hindered dislocation movement and promoted dynamic recrystallization during high-temperature wear.
MATERIALS CHARACTERIZATION
(2024)
Article
Materials Science, Multidisciplinary
Jubert Pasco, Lu Jiang, Thomas Dorin, Ali Keshavarzkermani, Youliang He, Clodualdo Aranas Jr
Summary: The unique structure and solute distribution of CoCrMo alloys produced using Laser Powder Bed Fusion technique require custom heat-treating processes to achieve the targeted phase distribution and mechanical properties. This study investigates the phase transformation behavior and precipitate distribution of CoCrMo samples after aging heat treatment. The results show differences in phase fraction and nucleation sites between directly aged and solution heat-treated samples.
MATERIALS CHARACTERIZATION
(2024)
Article
Materials Science, Multidisciplinary
Zipeng Ma, Meng Zhou, Baohong Tian, Yi Zhang, Heng Li, Xu Li, Jin Zou, Haoyan Hu, Ke Jing, Yong Liu, Alex A. Volinsky
Summary: In this study, two electrical contact composites were prepared using the vacuum hot pressing sintering endo-oxidation method. The addition of Y2O3 had no negative effects on the electrical conductivity and hardness of the composites. Moreover, it reduced the welding force and arc energy, and improved the stability of the contacts.
MATERIALS CHARACTERIZATION
(2024)
Article
Materials Science, Multidisciplinary
Wei Sun, Ning Cui, Shuling Zhang, Tiewei Xu, Xiaopeng Wang, Fantao Kong
Summary: A laminated composite was successfully fabricated and its microstructure and mechanical properties were investigated. The composite exhibited high bonding strength, improved flexural strength and fracture toughness, and superior tensile properties compared to the monolithic alloy.
MATERIALS CHARACTERIZATION
(2024)
Article
Materials Science, Multidisciplinary
Zih-You Wu, Yin-Ku Lee, Su-Yueh Tsai, Po-Yu Chen, Jenq-Gong Duh
Summary: With the development of the artificial intelligence (AI) industries, electronic packaging is advancing towards high density, high efficiency, and multi-functionality. The application of microbumps is necessary to achieve high density and small-scale interconnection. In this study, three types of full intermetallic compounds (IMCs) bumps were fabricated, and the mechanical and thermal properties of IMCs were analyzed. The results showed that the full IMCs bumps with added Ni and Zn exhibited consistent structure and excellent thermal stability, providing a reliable microstructure for application.
MATERIALS CHARACTERIZATION
(2024)