Article
Chemistry, Physical
Wenwen Zhang, Xingang Liu, Mengying Zhu, Ying Guo, Heyong Qin, Qiang Tian
Summary: In this study, the effect of coupling hot deformation and heat treatment on the morphology of gamma' precipitates in GH4742 superalloy was investigated. The results show that after subsolid solution heat treatment and rapid cooling, tri-modal size distribution of gamma' precipitates was observed, with dendritic primary gamma' precipitates. The morphology of gamma' precipitates within deformed grains is influenced by the accumulation of dislocations and other defects. The maximum size of columnar gamma' precipitates is obtained at high-angle grain boundaries. The stable morphology and size of gamma' precipitates at sigma 3 twin boundaries were also observed. These findings provide important insights for the design and optimization of Ni-base superalloys.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Qingshuai Feng, You Wu, Jikang Li, Yunfei Cai, Yuanyuan Zhang, Jiantao Liu, Tong Liu
Summary: By regulating the intermediate temperature and employing interrupted cooling during solution treatment, serrated grain boundaries and fine gamma' precipitates can be achieved in a nickel-based powder superalloy, leading to improved properties.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Nanoscience & Nanotechnology
Hongkai Zhang, Hechuan Ma, Tianxing Chang, Yang Zhang, Roland E. Loge, Qi Zhang, Xuewei Fang, Ke Huang
Summary: Coarse gamma ' precipitates in nickel-based superalloys, previously considered to be non-deformable, were found to undergo deformation through the 1/6 < 112 > Shockley partial dislocation shear mechanism, as revealed by transmission electron microscopy analysis and molecular dynamics simulation.
SCRIPTA MATERIALIA
(2023)
Article
Chemistry, Physical
Lihua Zhu, Hao Pan, Junyi Cheng, Lei Xiao, Jianzheng Guo, Hongjun Ji
Summary: The effect of cooling rate after super-solvus heat treatment on the morphological evolution of gamma' precipitates in an advanced powder metallurgy Ni-based superalloy was investigated. The relationship between cooling rate and gamma' precipitates was quantitatively analyzed. The results showed that cooling rate influenced the primary and secondary dendritic orientations of gamma' precipitates. Additionally, the width of the gamma' channel and the cooling rate affected the morphology and evolution of the gamma' precipitates.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Chemistry, Physical
Christian Voelter, Joachim Rosler
Summary: The study introduces a method for producing nanoporous superalloy membranes and discusses the mechanical properties of polycrystalline membranes, finding that their strength exceeds that of single-crystalline membranes despite the significantly higher pore volume content.
Article
Materials Science, Multidisciplinary
Jiachen Xu, Xinbao Zhao, Weiqi Li, Hao Liu, Quanzhao Yue, Huanchang Duan, Yuefeng Gu, Ze Zhang
Summary: This study investigates the effects of aging temperatures and aging times on the precipitation and morphological evolution of γ' precipitates in a 4th generation nickel-based single crystal superalloy (Ni-SX). The results show that the primary aging temperature and secondary aging time dominate the size and squareness of γ' precipitates respectively. The optimized aging process of Ni-SX is determined to be 1100-1120°C/4 h and 870°C/16 h.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Aliakbar Fallah Sheykhlari, Hossein Arabi, Seyed Mohammad Ali Boutorabi
Summary: The abnormal directional growth and coalescence of the gamma' phase in CoNiAlW superalloy during aging without applied stress were investigated. Microstructural evaluations showed that close precipitates coalesced over time. Elastic strain energy was identified as the driving force behind the coalescence, which was confirmed by reducing the lattice misfit between gamma and gamma' phases. A mechanism for the directional coalescence of gamma' precipitates was proposed, and the critical channel width for coalescence was described in terms of lattice misfit, interfacial energy, and volumetric free energy. The results revealed that the extent of coalescence decreases with decreasing lattice misfit in this positively misfit superalloy.
MATERIALS CHARACTERIZATION
(2023)
Article
Materials Science, Multidisciplinary
R. Buerstmayr, F. Theska, R. Webster, M. Lison-Pick, S. Primig
Summary: The performance of Ni-based superalloys is affected by the presence of precipitates at grain boundaries, especially in alloys like Rene 41 with high alloying elements. Different types of grain boundary carbides may exist at different temperatures, highlighting the significance of understanding these precipitates for manufacturing high-quality aerospace components.
MATERIALS CHARACTERIZATION
(2021)
Article
Nanoscience & Nanotechnology
Yongchao Gai, Rui Zhang, Jinxia Yang, Chuanyong Cui, Jinglong Qu
Summary: The effects of different heat treatments on the microstructures and mechanical properties of a wrought superalloy GH4151 were investigated. The solution treatments influenced the area fraction of gamma' precipitates and the grain size of the matrix. A dissolution kinetics model of primary gamma' precipitates was calculated. It was found that the fine primary gamma' precipitates dissolved first when the solution temperature was below 1120 degrees C, while the coarse primary gamma' precipitates dissolved noticeably when the solution temperature was above 1130 degrees C. Additionally, grain growth occurred at solution temperatures above 1130 degrees C. Furthermore, a higher area fraction of secondary gamma' precipitates with increased size was observed with higher solution temperatures. Tensile tests revealed that the alloy solution treated at 1130 degrees C possessed the optimum tensile properties at 750 degrees C due to the high area fraction of medium-sized secondary gamma' precipitates.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Lukasz Rakoczy, Malgorzata Grudzien-Rakoczy, Fabian Hanning, Grzegorz Cempura, Rafal Cygan, Joel Andersson, Anna Zielinska-Lipiec
Summary: During short-term annealing of the equiaxed Ni-based superalloy Rene 108, gamma ' precipitates dissolution occurred more rapidly at higher temperatures, leading to a decrease in the surface fraction of gamma ' precipitates. The dissolution process involved both thinning of individual precipitates and more complex mechanisms such as splitting.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2021)
Article
Nanoscience & Nanotechnology
Hongkai Zhang, Yan Li, Hechuan Ma, Peng Zhang, Tengfei Ma, Ke Huang
Summary: A new manufacturing method that only involves pre-annealing and hot deformation steps is proposed in this study, which successfully modulates diverse nanoscale precipitation strengthening phases with similar grain sizes. The modulated alloys exhibit high strength without the need for lengthy post-processing treatments.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Metallurgy & Metallurgical Engineering
Hyung-Won Park, Kyunghyun Kim, Hyeon-Woo Park, Akira Yanagida, Jun Yanagimoto
Summary: This study aims to formulate a constitutive equation to accurately determine the flow stress of superalloy 718 for effective production of gas turbine disks. A hot-compression test was conducted to analyze the flow stress in the dynamic precipitation region. A new constitutive equation for the generalized flow curve of superalloy 718 was obtained by considering these metallurgical phenomena.
ISIJ INTERNATIONAL
(2023)
Article
Materials Science, Multidisciplinary
Hongkai Zhang, Yan Li, Tengfei Ma, Tianxing Chang, Peng Zhang, Xuewei Fang, Ke Huang
Summary: This study investigates the tensile properties of GH4720Li nickel-based superalloy samples with bimodal and trimodal gamma' precipitates distributions. The characteristics of the precipitates were quantified and the deformation microstructures were examined. The results show that tertiary gamma' contributes significantly to the strength of the alloy, while the contribution of secondary y' depends on particle size and competition between different shear mechanisms. The correlations between yield strength, deformation mechanism, and particle size are discussed, providing insights for the strength optimization of multimodal-particle-containing alloys.
MATERIALS CHARACTERIZATION
(2022)
Article
Nanoscience & Nanotechnology
Mitsuki Obana, Kartik Prasad, Atsushi Ito, Shiro Torizuka
Summary: In this study, three dimensional parts of Inconel 718 superalloy were fabricated using L-PBF additive manufacturing. Tensile tests and microstructure characterization were conducted to compare the mechanical properties of AM IN 718 and W IN 718, showing a marginal increase in yield strength for AM IN 718.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Materials Science, Multidisciplinary
Anthony De Luca, Christoph Kenel, Seth Griffiths, Shreyas S. Joglekar, Christian Leinenbach, David C. Dunand
Summary: Additive manufacturing of non-weldable high-gamma' Ni base superalloys faces challenges due to their inherent cracking propensity. The segregation of melting point-depressant elements to grain boundaries drastically increases the solidification interval and leads to solid-state cracking at high-angle GBs. The study found that Ti, Cr, and Al segregate to solidification cell boundaries, while the formation of oxide and sulfide precipitates influences the alloy performance.
MATERIALS & DESIGN
(2021)
Article
Materials Science, Multidisciplinary
H. P. Ng, P. Nandwana, A. Devaraj, M. Samblanet, S. Nag, P. N. H. Nakashima, S. Meher, C. J. Bettles, M. A. Gibson, H. L. Fraser, B. C. Muddle, R. Banerjee
Correction
Materials Science, Multidisciplinary
H. P. Ng, P. Nandwana, A. Devaraj, M. Semblanet, S. Nag, P. N. H. Nakashima, S. Meher, C. J. Bettles, M. A. Gibson, H. L. Fraser, B. C. Muddle, R. Banerjee
Article
Materials Science, Multidisciplinary
Yufeng Zheng, Robert E. A. Williams, Dong Wang, Rongpei Shi, Soumya Nag, Pavani Kami, John M. Sosa, Rajarshi Banerjee, Yunzhi Wang, Hamish L. Fraser
Article
Materials Science, Multidisciplinary
B. P. Bewlay, S. Nag, A. Suzuki, M. J. Weimer
MATERIALS AT HIGH TEMPERATURES
(2016)
Article
Nanoscience & Nanotechnology
Yufeng Zheng, Robert E. A. Williams, Soumya Nag, Rajarshi Banerjee, Hamish L. Fraser, Dipankar Banerjee
SCRIPTA MATERIALIA
(2016)
Article
Nanoscience & Nanotechnology
S. Meher, G. B. Viswanathan, S. Nag, H. L. Fraser, R. Banerjee
SCRIPTA MATERIALIA
(2016)
Article
Engineering, Manufacturing
R. Conteri, T. Borkar, S. Nag, D. Jaeger, X. Chen, R. V. Ramanujan, R. Banerjee
JOURNAL OF MANUFACTURING PROCESSES
(2017)
Article
Chemistry, Physical
T. Rojhirunsakool, A. R. P. Singh, S. Nag, J. Y. Hwang, J. Tiley, R. Banerjee
Article
Materials Science, Multidisciplinary
Tanaporn Rojhirunsakool, Soumya Nag, Rajarshi Banerjee
Article
Chemistry, Physical
Tushar Borkar, Soumya Nag, Yang Ren, Jaimie Tiley, Rajarshi Banerjee
JOURNAL OF ALLOYS AND COMPOUNDS
(2014)
Article
Materials Science, Multidisciplinary
D. Choudhuri, N. Dendge, S. Nag, S. Meher, T. Alam, M. A. Gibson, R. Banerjee
JOURNAL OF MATERIALS SCIENCE
(2014)
Article
Materials Science, Multidisciplinary
Casey Smith, Shravana Katakam, Soumya Nag, Xi Chen, Raju V. Ramanujan, Narendra B. Dahotre, Rajarshi Banerjee
Article
Materials Science, Multidisciplinary
Soumya Nag, Yiming Zhang, Sreekar Karnati, Lee Kerwin, Alex Kitt, Eric MacDonald, Dora Cheung, Neil Johnson
Summary: The study uses a feature-based qualification method to reduce the cost and time of DED process qualification. A hybrid-physics-based multi-objective optimization tool is used to predict processing-structure-property relationships in thin-walled builds. The probabilistic ML models achieved targeted predictions with higher reliability compared to conventional methods.
Article
Engineering, Multidisciplinary
Yiming Zhang, Sreekar Karnati, Soumya Nag, Neil Johnson, Genghis Khan, Brandon Ribic
Summary: This paper introduces a surrogate modeling approach based on experimental data to improve the design efficiency in additive manufacturing (AM) processes. The effectiveness and practicality of the method are demonstrated through its application to multiple benchmark designs of direct energy deposition (DED), including forward prediction, global sensitivity analysis, backward prediction and optimization, and intelligent data addition.
ASCE-ASME JOURNAL OF RISK AND UNCERTAINTY IN ENGINEERING SYSTEMS PART B-MECHANICAL ENGINEERING
(2022)
Article
Materials Science, Multidisciplinary
Soumya Nag, Brian Jordan, Ke An, Jaimie Tiley, Chuan Zhang, Fan Zhang
Summary: A new approach has been developed to fabricate parts with specific properties for use in extreme environments in the aviation, space, and energy sectors.
ADVANCED MATERIALS & PROCESSES
(2022)