Article
Chemistry, Physical
Yixuan He, Yuhao Wu, Fan Bu, Yiyuan Zhang, Yifan Zhang, Bo Hei, Jianbao Zhang, Haifeng Wang
Summary: This study systematically explores the solidification pathways, microstructural evolution, and recalescence behaviors of undercooled Co-18.5at.%B eutectic alloys. The results reveal four possible solidification pathways and provide explanations for the microstructural evolution and phase selection. Additionally, prenucleation of the primary phase is detected through analysis of the recalescence behaviors.
Article
Materials Science, Multidisciplinary
L. J. Liu, S. Y. Lu, Q. Y. Qin, L. Yang, J. F. Li
Summary: This study investigated the solidification process of Ni75B25 alloy under different undercooling conditions and identified the formation and transformation mechanism of the Ni23B6 phase. It was found that the alloy solidifies completely into Ni3B phase when the undercooling is less than 240K. At larger undercooling, the metastable Ni23B6 phase primarily forms in the melt but then decomposes into alpha-Ni and Ni3B through a eutectoid reaction. The delay time between the two temperature recalescence events affects the amount of residual liquid and the recalescence temperature.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
Yan Chong, Jangho Yi, Guanyu Deng, Nobuhiro Tsuji
Summary: The aging behavior of Ti-1.0 wt pct Fe alloy was studied in this research, focusing on microstructural modifications within the beta grains. At lower aging temperatures, omega(ath) precipitates gradually decreased and were replaced by alpha(s) precipitates. At higher aging temperatures, alpha(s) precipitates increased in size while their volume fraction decreased, indicating a partial alpha to beta reverse phase transformation. The presence of omega(ath) promoted a homogeneous precipitation behavior of alpha(s) precipitates, leading to the formation of plate-shaped alpha(s) precipitates with multiple crystallographic variants.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
Lianjie Liu, Lin Yang, Jinfu Li
Summary: Up to five solidification pathways were identified in the undercooled solidification of Co79.3B20.7 alloy. The primary phase evolves from Co3B to Co2B to Co23B6, and finally to alpha-Co/Co3B eutectic as undercooling prior to nucleation increases. The phase competition was interpreted based on nucleation theories.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2021)
Article
Materials Science, Multidisciplinary
Jinge Yan, Tie Liu, Jing Liao, Jinmei Sun, Xiaoyu Guo, Zhongming Ren, Qiang Wang
Summary: The study investigated the solute migration behavior in the mushy zone of Al-18 at. pct Ni alloy under a high magnetic field. It found that the magnetic field significantly altered the morphology and precipitation behavior of the peritectic phase. The results showed that the magnetic field hindered solute migration, leading to changes in the peritectic interface and enrichment of Ni atoms.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2021)
Article
Metallurgy & Metallurgical Engineering
Wei LI, Xiu-xun Wei, Jin-fu LI
Summary: The relationship between anomalous eutectic and the remelting of the primary phase in Ni-19.6at.%P eutectic alloy was investigated. Fully regular eutectic structures were obtained when thin samples were solidified over a range of undercoolings with temperature recalescence depressed. Rapidly heating the thin samples to certain temperatures between the nucleation and eutectic temperatures resulted in anomalous eutectic structure. It was found that the volume fraction of anomalous eutectic increased with increasing target temperature, with alpha-Ni particulates randomly oriented and beta-Ni3P phase well oriented in the anomalous eutectic formed upon heating.
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
(2023)
Article
Materials Science, Multidisciplinary
Yumin Wang, Shuangming Li, Cong Cao, Zhongli Liu, Hui Xing
Summary: In this study, the effect of kinetic on seaweed pattern formation in an Al-2 wt pct Si alloy during laser surface remelting was investigated. The results showed that interface energy and kinetics play important roles in the growth of cellular patterns. A high-temperature gradient promotes the formation of degenerate seaweed, while an increase in scanning velocity leads to a transition from degenerate to hyperbranched seaweed.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2023)
Article
Physics, Applied
Q. Wang, C. H. Zheng, M. X. Li, L. Hu, H. P. Wang, B. Wei
Summary: The phase selection mechanism in undercooled liquid Nb90Si10 hypoeutectic alloy was investigated using electrostatic levitation technique combined with deep neural network molecular dynamics. The results showed that the intermetallic phase of the eutectic structure transformed from Nb3Si to beta Nb5Si3, and finally into alpha Nb5Si3 with increased liquid undercooling. The phase selection was mainly controlled by the short-range order of the residual liquid, with the predominant short-range configuration transforming from Nb3Si-like to Nb5Si3-like structures. The competitive nucleation of the aNb(5)Si(3) and beta Nb5Si3 phases was significantly influenced by the alpha Nb5Si3-like medium-range order.
APPLIED PHYSICS LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Changsong Ma, Lin Yang, Jinfu Li
Summary: This paper investigates the phase selection and microstructure evolution of Fe75B25 alloy during solidification at different undercoolings. The alloy consistently solidifies into a primary Fe2B phase and a-Fe/Fe2B eutectic at all the experimental undercoolings up to 381 K. Despite favorable conditions for the growth of metastable Fe3B phase, it does not precipitate in this alloy. The phase selection is found to be nucleation-controlled, with solid sites in the alloy melt favoring the nucleation of the Fe2B phase. The morphology of the Fe2B phase changes complexly as undercooling increases, transitioning from coarse faceted dendrites to developed non-faceted dendrites, seaweeds with dense branches, and finally refined granular grains above 147 K.
Article
Materials Science, Multidisciplinary
Tingting Yan, Kuisong Zhu, Lei Zhou, Kuixian Wei
Summary: This study proposes a method for preparing C54-TiSi2 using electromagnetic directional solidification technology, successfully achieving preparation without intermediate compounds. Through the analysis of lattice parameters, phase separation law, and impurity bias ability, the purity of C54-TiSi2 and removal rates of iron and aluminum were confirmed, and silicon was identified as the key impurity hindering further purification.
METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
(2022)
Article
Chemistry, Physical
N. A. Belov, T. K. Akopyan, N. O. Korotkova, P. K. Shurkin, V. N. Timofeev, O. A. Raznitsyn, T. A. Sviridova
Summary: The Al-3.3Cu-2.5Mn-0.5Zr alloy exhibited excellent processability during cold rolling and drawing, as well as high mechanical properties and electrical conductivity after annealing at 400 degrees C, due to the large deformation during rolling and the high fraction of nano dispersoids. Annealing at temperatures between 350 and 400 degrees C allowed for achieving equilibrium compositions in a reasonable time, while lower temperatures required much longer exposure times for diffusion of Zr in Al.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Chemistry, Multidisciplinary
Xuan Ge, Qiaodan Hu, Fan Yang, Jun Xu, Yanfeng Han, Pingsheng Lai, Jingyu Qin, Jianguo Li
Summary: The study investigates the polymorphism in the crystallization processes of titanates, specifically focusing on the nucleation selection between cubic and hexagonal phases during the crystallization of barium titanate. The researchers found that the intrinsic structure property of the melt, particularly the degree of polymerization between Ti-O polyhedra, plays a crucial role in regulating the polymorphic selection. This innovative perspective provides insights into the non-isomorphic structure transitions of the melt beyond the traditional cognition of structural heredity.
COMMUNICATIONS CHEMISTRY
(2021)
Article
Metallurgy & Metallurgical Engineering
Chongfeng Sun, Shengqi Xi, Xiaofeng Dang, Jianping Li, Yongchun Guo, Zhong Yang, Yaping Bai
Summary: This paper comprehensively studies the microstructure characteristics and phase transitions of Fe-19 wt%Cr-9 wt%Ni nanocrystalline alloy during mechanical alloying and hot pressing sintering processes. The corrosion resistance of the sintered alloy samples is further analyzed and shows excellent properties compared to commercial 304 stainless steel.
ACTA METALLURGICA SINICA-ENGLISH LETTERS
(2021)
Article
Chemistry, Physical
He Zhang, Jun-Ru Liu, Guo-Hua Zhang
Summary: This study successfully prepared high-performance W-Cu-Ni-Fe alloys with the addition of Ni and Fe using low temperature liquid-phase sintering. The additions of Ni and Fe improved the bonding strength and wettability of the alloy, resulting in enhanced mechanical properties. Moreover, the Ni and Fe additions also increased the compressive strength and solid solution strengthening effects of the alloy. However, it led to a decrease in the electrical conductivity.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
Yaqi Guo, Sen Luo, Weiling Wang, Miaoyong Zhu
Summary: A GPU-accelerated 3D PF-LBM model was established to predict multi-dendritic growth of Fe-C binary alloy, overcoming limitations of GPU memory and achieving a speedup ratio of 1700 times. Results showed that under forced fluid flow, solute enrichment at the interdendritic space was hardly washed away, leading to more significant solute enrichment in the downstream region.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Thermodynamics
Zhenting Liu, Junfeng Xu, Yaling Wang, Zengyun Jian, Jiangnan Liu
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2018)
Article
Thermodynamics
Zhenting Liu, Junfeng Xu, Yaling Wang, Zengyun Jian, Jiangnan Liu
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2018)
Article
Materials Science, Multidisciplinary
Junfeng Xu, Zengyun Jian, Bo Dang, Di Zhang, Feng Liu
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2017)
Article
Optics
Zhenting Liu, Junfeng Xu, Yaling Wang, Zengyun Jian, Jiangnan Liu
Article
Mathematics, Applied
Junfeng Xu, Peter K. Galenko
Summary: Experimental data on rapid solidification of eutectic systems show the formation of metastable solid phases due to suppression of eutectic decomposition by diffusionless solidification. A model considering diffusionless growth is developed to analyze atomic diffusion in lamellar eutectic couples growing into supercooled liquid. The model reveals two regimes based on the solid-liquid interface velocity and characteristic diffusion speed in the bulk liquid.
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2021)
Article
Thermodynamics
Junfeng Xu, Ying Xiao, Zengyun Jian
Summary: This study utilizes high-speed camera technology for temperature evolution investigation, which can provide higher accuracy temperature profiles and analyze temperature profiles of small melt-pool and subsequent rapid solidification process in additive manufacturing. Additionally, the relationship between recalescence rate and solidification interface is discussed.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2021)
Article
Mathematics, Applied
Junfeng Xu, Markus Rettenmayr, Peter K. Galenko
Summary: The developed model describes diffusion-limited and diffusionless solidification of a eutectic alloy, providing new expressions for solute distribution coefficient and liquidus lines slope. The model's predictions are compared with experimental data for Fe-B alloy solidification, showing good agreement especially for low and high undercoolings. The influence of model parameters on growth kinetics during eutectic solidification is discussed.
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2021)
Article
Mathematics, Applied
Junfeng Xu, Dandan Fan, Tao Zhang
Summary: This study investigated the influences of superheating temperature on the nucleation undercooling of metallic melts through molecular dynamics simulations. The results showed that extremely high heating rates and short equilibration time lead to superheating and partial melting of the solid phase. The proportion of crystalline clusters in the superheated phase depends on the superheating temperature and equilibration time, with a subsequent fast cooling facilitating substantial undercooling of the molten phase.
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2021)
Article
Mathematics, Applied
Junfeng Xu, Tao Zhang, Peter K. Galenko
Summary: This article introduces an analytical model to understand the rod growth of eutectic in the bulk undercooled melt, aiming to predict transitions in eutectic patterns under different growth velocities, and presents mathematical simplifications for solving Bessel functions as the most important priority for model calculation.
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2022)
Article
Multidisciplinary Sciences
Peter K. Galenko, Junfeng Xu
Summary: This study investigates the formation mechanism of metastable solid phases in rapidly solidified eutectic systems. It proposes a diffusionless growth model to suppress eutectic decomposition and analyzes atomic diffusion in the growth of rod eutectics. A simplified calculating method for the Bessel function in the growth equation is also obtained, which can be applied to other rod eutectic growth models.
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
(2022)
Article
Instruments & Instrumentation
Junfeng Xu, Baodong Zhang, Jitao Cao, Wenwen Fan, Zhirui Yao, Xuyang Li
Summary: The mechanical and thermal properties of glass can be significantly influenced by the addition of CsI. The optical properties, hardness, fracture toughness, and other characteristics change with the increase in CsI content. Additionally, the hardness and fracture toughness of the glass can be greatly improved by maintaining the glass at a certain temperature for a period of time.
INFRARED PHYSICS & TECHNOLOGY
(2022)
Article
Metallurgy & Metallurgical Engineering
Junfeng Xu, Jitao Cao, Tongzhuang Niu, Zhirui Yao, Xuyang Li
Summary: A novel method combining high-frequency induction and high-speed camera is proposed to measure the volume change of high temperature melt, especially for undercooled solidification. The changes of liquid and solid volume of binary Ni-B and ternary Fe-Ni-B alloy with temperature were studied. The influence of undercooling on volume change before and after solidification for primary and eutectic transitions is discussed.
TRANSACTIONS OF THE INDIAN INSTITUTE OF METALS
(2023)
Article
Crystallography
Junfeng Xu, Peter K. Galenko
Summary: This paper presents a solidification growth model that combines the effect of eutectic transformation and off-eutectic composition, and discusses the influence of model and material parameters on solidification kinetics by comparing them with experimental data. The computational results show that the off-eutectic growth model agrees well with experimental data on the solidification kinetics of Ni-B and Ti-Si alloys.
Article
Crystallography
Tongzhuang Niu, Junfeng Xu, Zhirui Yao, Zengyun Jian, Peter K. Galenko
Summary: This article proposes a method for measuring and analyzing the volume and density changes in high-temperature alloy melts using high-speed photography and computer MATLAB program image analysis technology. These techniques will aid in understanding the variations in the volume and density of high-temperature melt samples during the phase transition process.
Article
Materials Science, Multidisciplinary
Liu Zhenting, Xu Junfeng, Wang Yaling, Jian Zengyun, Liu Jiangnan
RARE METAL MATERIALS AND ENGINEERING
(2019)