Article
Materials Science, Multidisciplinary
D. Schimbaeck, J. Braun, G. Leichtfried, H. Clemens, S. Mayer
Summary: The study focused on investigating the processability and microstructural features of a powder-based TNM alloy with high Al content, as well as developing a tailored heat treatment to adjust the microstructure for balanced mechanical properties. The research showed that process parameters directly influence the microstructure, and post-processing heat treatment can tailor the microstructure to achieve specific properties.
MATERIALS & DESIGN
(2021)
Article
Engineering, Manufacturing
Saket Thapliyal, Shivakant Shukla, Le Zhou, Holden Hyer, Priyanshi Agrawal, Priyanka Agrawal, Mageshwari Komarasamy, Yongho Sohn, Rajiv S. Mishra
Summary: This study demonstrates that integrating grain refinement through heterogeneous nucleation and eutectic solidification in the Al-Ni-Ti-Zr alloy can produce crack-free parts across a wide range of process parameters, microstructural heterogeneity, and hierarchy. This approach targets hot cracking at multiple stages of solidification in L-PBF, as opposed to traditional alloy design strategies that focus on specific stages of solidification. The Al-Ni-Ti-Zr alloy shows excellent printability and high tensile performance, with the potential for fine-tuning microstructure and performance.
ADDITIVE MANUFACTURING
(2021)
Article
Materials Science, Multidisciplinary
Takahiro Kimura, Tomoatsu Ozaki, Takayuki Nakamoto, Takao Miki, Isao Murakami, Akiei Tanaka, Yoshiki Hashizume
Summary: A new heat-resistant alloy, Al-8mass%Mn-2mass%Cr, was produced using laser-based powder bed fusion. The alloy exhibited increased Vickers hardness and excellent high-temperature strengths after aging heat treatments at >=250 degrees C. The microstructure analysis revealed that the strong texture of coarse columnar crystal grains and the presence of precipitates at cell boundaries contributed to the strengthening effects in the alloy.
MATERIALS CHARACTERIZATION
(2023)
Article
Nanoscience & Nanotechnology
Feipeng Yang, Jianying Wang, Tao Wen, Lei Zhang, Xixi Dong, Dong Qiu, Hailin Yang, Shouxun Ji
Summary: The AM aluminium alloy Al5Mg3Zn2Si developed in this work exhibits high strength, ductility, and excellent mechanical properties without the addition of costly alloying elements. With an optimized relative density and refined microstructure, it has great potential for automotive and aerospace applications.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Tobias Ullsperger, Yannick L. Wencke, Burak Yuerekli, Gabor Matthaeus, Markus Rettenmayr, Gerrit A. Luinstra, Stefan Nolte
Summary: Laser-based additive manufacturing of UHMWPE using ultrashort laser pulses at a wavelength of 1030 nm expands the processing window and improves physical properties. Multi-photon absorption processes increase absorption locally, allowing for control over pulse energy and repetition rate to achieve polymer particle fusion. Preliminary tensile tests on produced specimens show an ultimate tensile strength of 4 MPa, surpassing values obtained using a CO2 laser.
MATERIALS & DESIGN
(2021)
Article
Nanoscience & Nanotechnology
F. Belelli, R. Casati, F. Larini, M. Riccio, M. Vedani
Summary: A novel high-strength aluminium alloy was designed in this study, with improved solidification behavior and uniform microstructure achieved by adding Ti and B to modify the chemical composition of the widely used 2618 alloy. After optimization, both the new alloy and the A20X alloy displayed high density and crack-free microstructures.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Metallurgy & Metallurgical Engineering
Anna Dobkowska, Lukasz Zrodowski, Monika Chlewicka, Milena Koralnik, Boguslawa Adamczyk-Cieslak, Jakub Ciftci, Bartosz Moronczyk, Miroslaw Kruszewski, Jakub Jaroszewicz, Dariusz Kuc, Wojciech Swieszkowski, Jaroslaw Mizera
Summary: In this study, powder metallurgy methods were used to fabricate Mg-7.5Li-3Al-Zn alloys from repowdered extruded alloys. LPBF and PPS processes were employed to consolidate the bulk materials. The LPBF and PPS materials exhibited refined microstructures but had drawbacks of porosity and unrecrystallized particle boundaries, which affected their corrosion resistance. However, powder metallurgy routes show great potential for the manufacture of Mg-Li based alloys.
JOURNAL OF MAGNESIUM AND ALLOYS
(2022)
Article
Materials Science, Multidisciplinary
Feipeng Yang, Jianying Wang, Tao Wen, Xinhai Ai, Xixi Dong, Hailin Yang, Shouxun Ji
Summary: The traditional wrought Al-Mg-Si alloys fabricated via laser powder bed fusion (LPBF) are prone to hot cracks, unless adding grain refiners in as-LPBFed Al alloys. In this work, the Al-9.6 wt.% Mg-4.9 wt.% Si alloy with low solidification range and hot-cracking susceptibility was successfully processed by LPBF. The as-LPBFed alloys have reached a high relative density of 99.3% at the VED of 129.6 J/mm(3). The microstructures were featured by fine a-Al grains and cellular eutectic Mg2Si, accompanied by a high number density of dislocations, coherent GP zone and alpha-Al-12(Fe, Mn)(3) Si phases. The as-LPBFed Al-13.3Mg(2)Si alloy exhibited the high ultimate tensile strength of 557 MPa, yield strength of 439 MPa and elongation of 2.9%. In addition to the grain refinement and dislocation strengthening, the strength enhancement is mainly ascribed to the dispersion strengthening from the divorced nanosized eutectic Mg2Si. The results demonstrate that manipulation of alloys at near eutectic composition is effective to achieve high strength Al-Mg-Si alloys processed by LPBF.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Engineering, Manufacturing
Douglas M. Sassaman, Matthew S. Ide, Joseph J. Beaman, Desiderio Kovar
Summary: By analyzing video images captured during LPBF processing of nylon/alumina blends, we propose a mechanistic model based on permeation to predict the conditions required for particle bonding in indirect LPBF. Experimental results confirm the accuracy of the model.
ADDITIVE MANUFACTURING
(2022)
Article
Materials Science, Multidisciplinary
L. Xue, K. C. Atli, C. Zhang, N. Hite, A. Srivastava, A. C. Leff, A. . A. . Wilson, D. J. Sharar, A. Elwany, R. Arroyave, I. Karaman
Summary: Laser powder bed fusion is a promising additive manufacturing technique for fabricating complex NiTi shape memory alloy parts. This study successfully achieved room temperature tensile superelasticity in as-printed NiTi parts by eliminating porosity and cracks, tailoring the evaporation of Ni, and controlling the oxygen content.
Article
Engineering, Manufacturing
Shuhan Li, Xinqiang Lan, Zemin Wang, Shuwen Mei
Summary: The study demonstrates that appropriate post-heat treatments can improve the mechanical properties of Ti-6.5Al-2Zr-Mo-V alloy processed by LPBF, especially ductility. By comparing samples obtained under different heat treatment conditions, the study investigated the effects of microstructure on mechanical properties.
ADDITIVE MANUFACTURING
(2021)
Article
Materials Science, Multidisciplinary
Yingang Liu, Jingqi Zhang, Qiyang Tan, Yu Yin, Shiyang Liu, Meng Li, Miaoquan Li, Qiong Liu, Ying Zhou, Tao Wu, Feng Wang, Ming-Xing Zhang
Summary: The high-strength Cu-Co alloys were fabricated using laser powder bed fusion (L-PBF) additive manufacturing, where the addition of cobalt submicron particles led to remarkable grain refinement through heterogeneous nucleation. The Cu-Co alloys demonstrated a combination of high strength and ductility, with tensile strength reaching up to 491.1 +/- 12.6 MPa after post L-PBF heat treatment, without sacrificing ductility.
Article
Engineering, Manufacturing
Francis Ogoke, Amir Barati Farimani
Summary: Powder-based additive manufacturing techniques offer a powerful tool for building intricate structures, but defects in Laser Powder Bed Fusion pose challenges. A Deep Reinforcement Learning framework is proposed to generate a versatile control policy that adjusts laser velocity or power to ensure melt pool consistency and prevent overheating in the final product.
ADDITIVE MANUFACTURING
(2021)
Article
Engineering, Manufacturing
B. Gao, H. Peng, H. Yue, H. Guo, C. Wang, B. Chen
Summary: This paper presents the utilization of multi-spot melt strategy combined with smaller layer thickness to produce Y2O3/γ-TiAl nanocomposite through additive manufacturing. Compared with the hatch melt, the multi-spot melt strategy leads to a lower proportion of γ and B2-phases, a smaller lamellar spacing with straight α2/γ interfaces, and a more uniform distribution of nanoparticles with a finer size. The formation of twins within the γ grains and γ lamellae is observed in both multi-spot and hatch melt samples. The as-built condition achieves a good combination of tensile strength, ductility, and fracture toughness. Quantitative microscopy confirms a homogeneous microstructure in the x-y plane for the multi-spot sample, and the smaller layer thickness helps reduce microstructure degradation during thermal cycling. TEM analysis identifies rod-like Y2O3 with a monoclinic crystal system and near-spherical Y2O3 with a cubic crystal system. The Y2O3/TiAl interface is found to be clean and free of interfacial reactions, suggesting strong bonding.
ADDITIVE MANUFACTURING
(2023)
Article
Engineering, Manufacturing
A. Jam, A. du Plessis, C. Lora, S. Raghavendra, M. Pellizzari, M. Benedetti
Summary: Additively manufactured lattice structures of titanium alloys, especially a novel beta-Ti alloy, are being studied for bone replacement implants due to their close match to bone elastic modulus and high ductility. This study focuses on investigating the manufacturability of lattice structures made from the new beta-Ti alloy and their potential for future implant applications.
ADDITIVE MANUFACTURING
(2022)
Review
Materials Science, Multidisciplinary
Prince V. Cobbinah, Wallace R. Matizamhuka
ADVANCES IN MATERIALS SCIENCE AND ENGINEERING
(2019)
Article
Automation & Control Systems
Prince Valentine Cobbinah, Wallace Matizamhuka, Ronald Machaka, Mxolisi Bredon Shongwe, Yoko Yamabe-Mitarai
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2020)
Review
Chemistry, Physical
Omoyemi Temitope Onawale, Prince Valentine Cobbinah, Rivel Armil Nzeukou, Wallace Rwisayi Matizamhuka
Summary: Microstructural phase evolution in HEAs during melting and casting is influenced by cooling rate, constituent elements, and binary pairs. Processing routes and parameters impact the mechanical properties. The microstructure of alloys is affected by various factors, requiring thorough investigation and consideration.
Review
Materials Science, Multidisciplinary
Prince Valentine Cobbinah, Sae Matsunaga, Yoko Yamabe-Mitarai
Summary: This review presents the research progress in the laser powder bed fusion (LPBF) process and the control of crystallographic texture, as well as the influence of process parameters on texture and microstructural evolution, and the effects on properties.
ADVANCED ENGINEERING MATERIALS
(2023)
Proceedings Paper
Materials Science, Multidisciplinary
Prince Valentine Cobbinah, Wallace Matizamhuka, Ronald Machaka, Mxolisi Brendon Shongwe, Yoko Yamabe-Mitarai
Summary: By mechanical alloying and spark plasma sintering, c-TiAl based alloys with different Ta contents were fabricated in this study. The results showed that the addition of Ta improved the compressive strength of the alloys, especially at high temperatures. The mode of failure for all sintered alloys at 850°C and above was intergranular fracture.
MATERIALS TODAY-PROCEEDINGS
(2021)
Article
Multidisciplinary Sciences
P. Cobbinah, W. R. Matizamhuka
SN APPLIED SCIENCES
(2019)
