Article
Metallurgy & Metallurgical Engineering
Fei Guo, Cheng-Wu Zheng, Pei Wang, Dian-Zhong Li, Yi-Yi Li
Summary: It is found in this study that under low-oxygen conditions, the addition of trace rare earth elements can significantly influence the nucleation, morphology, and growth of ferrite in Fe-0.14%C alloy, by slowing down carbon diffusion and decreasing grain boundary energy. This research provides evidence for adjusting phase transformation and improving the mechanical properties of steels through the addition of rare earth elements.
ACTA METALLURGICA SINICA-ENGLISH LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Henry Martin, Peter Amoako-Yirenkyi, Aarne Pohjonen, Nana K. Frempong, Jukka Komi, Mahesh Somani
Summary: The article introduces a statistically developed model for austenite decomposition during cooling, which incorporates two-way interactions of alloying elements as add-on terms. This model can predict phase transformation temperatures and critical cooling rates for the formation of polygonal ferrite, bainite or martensite in steel production.
METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
(2021)
Article
Materials Science, Multidisciplinary
M. Enomoto
Summary: This study investigated the kinetic transition of partitionless proeutectoid ferrite transformation from austenite in an Fe-C-Mn-Si alloy. By incorporating interfacial segregation of carbon and alloy elements, the time-dependent diffusion equations of solutes were solved to evaluate the transient effects of solute accumulation on the migration of interface. It was found that the migration of interface ceased and stasis occurred when the carbon concentration gradient in the immediate front of the interface turned to null or reversed, leading to earlier transformation than predicted by conventional theory.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2021)
Article
Metallurgy & Metallurgical Engineering
Mitsutaka Sato, Takamasa Murata, Shota Shimaya, Goro Miyamot, Tadashi Furuhara
Summary: The ferrite transformation behavior of the Fe-0.3 mass%N binary alloy was studied, revealing the formation of different morphologies of ferrite at different temperatures and investigating the growth mechanisms and energy dissipation of different types of ferrite.
ISIJ INTERNATIONAL
(2021)
Article
Materials Science, Multidisciplinary
Li-bin Jin, Shu-guo Zheng, Miao-yong Zhu
Summary: The formation mechanism of AlN-MnS complex inclusions in Fe-5Mn-2Al-0.15C medium Mn steel under as-cast conditions was investigated through microstructure observation, thermodynamic analyses, and the Clyne-Kurz microsegregation model. The results showed that the variations in partition coefficients and diffusion coefficients of solute elements should be considered in the Clyne-Kurz model during the solidification process. The precipitation temperatures of AlN and MnS were determined as 1738 K and 1717 K, respectively, by the Clyne-Kurz model considering variable partition coefficients and diffusion coefficients.
Article
Nanoscience & Nanotechnology
Chaofan Zhang, Chenxi Liu, Hui Guo, Shaoheng Sun, Hao Chen, Yongchang Liu, Ran Ding
Summary: In this study, a chemical heterogeneity of Mn was introduced into the parent austenite of a Fe-0.2C-2Mn steel. By promoting C partitioning during the austenite to ferrite transformation, the Mn-rich regions in the parent austenite were substantially stabilized, resulting in a multiphase microstructure with improved strength and ductility. This provides a simple alternative route to acquire retained austenite in advanced high strength steels without the need of Si and Al alloying.
SCRIPTA MATERIALIA
(2022)
Article
Materials Science, Multidisciplinary
Chaojie Yan, Chenhua Yuan, Kai Wang, Xichen Yang, Tie Liu, Qiang Wang
Summary: The effects of a high magnetic field on the nucleation kinetics of proeutectoid ferrite have been studied using SEM equipped with Electron backscattering diffraction to analyze the quantity and morphology of proeutectoid ferrite. The results show that the nucleation density of proeutectoid ferrite increased by about 11-17% from 1033 to 993K. The increase in nucleation density is attributed to the magnetization energy induced by the high magnetic field. A relationship between magnetic flux density, temperature, and nucleation rate of proeutectoid ferrite is clarified based on the Weiss molecular field theory, and a nucleation kinetics model of proeutectoid ferrite under high magnetic fields is proposed.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2023)
Article
Materials Science, Multidisciplinary
Haijiang Hu, Guang Xu, Muhammad Nabeel, Neslihan Dogan, Hatem S. Zurob
Summary: The study found that the growth of bainitic ferrite laths can be affected by pre-existing laths, causing growth interruption and re-nucleation. The newly nucleated lath shares the same crystallographic orientation with the prior lath and is termed BF-clone. During growth, transformation strain is accommodated through the formation of twin-related variant pairs.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2021)
Article
Materials Science, Multidisciplinary
Xianguang Zhang, Goro Miyamoto, Yuki Toji, Yongjie Zhang, Tadashi Furuhara
Summary: The effects of cementite (theta) and retained austenite (RA) on the kinetics and microstructure evolution in austenite reversion have been studied in an Fe-2Mn-1.5Si-0.3C alloy. The results indicate that pre-tempering or prolonged austempering enhance the formation of globular gamma, while the presence of RA in short time austempered bainite structure suppresses it. High-temperature pre-tempering or prolonged austempering delays reversion kinetics, while low-temperature pre-tempering or the presence of RA have minimal effects on kinetics.
Article
Materials Science, Multidisciplinary
Lidong Xing, Xiaoyue Fan, Min Wang, Lihua Zhao, Yanping Bao
Summary: The study found that proeutectoid ferrite in medium-carbon sulfur-containing blooms is more developed compared to those with lower sulfur content, and sulfur is beneficial to the formation of ferrite. MnS inclusions serve as the core of proeutectoid ferrite, with the number of precipitated MnS inclusions positively correlated to the area fraction of proeutectoid ferrite. The Mn-depleted zone around MnS inclusions is identified as the direct inducing factor for proeutectoid ferrite formation in medium-carbon sulfur-containing blooms.
METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
(2021)
Article
Materials Science, Multidisciplinary
Yang Shen, Bo Chen, Cong Wang
Summary: The in situ Austenite -> bainite transformation in the coarse-grained heat-affected zone of 2.25Cr-1Mo steel has been documented using a confocal scanning laser microscope, and the kinetics of bainite growth has been quantified. Four typical nucleation sites of bainite laths have been identified. Moreover, the growth rate of nine distinctive bainite laths varies from 9 to 200 μm/s, depending on the degree of supercooling and nucleation sites of bainite laths.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2021)
Article
Materials Science, Multidisciplinary
Hongbo Pan, Weiming Liu, Huiting Wang, Yonggang Liu, Yaqiang Tian, Ke Chen, Xiaohui Shen, Hua Zhan, Xiangyang Mao, Yangyang Xiao, D. Y. Li
Summary: The study highlights the competition mechanism between ferritic recrystallization and austenitic transformation during intercritical annealing of Fe-Al-Mn-Mo-C deep drawing dual-phase steel. It was found that an appropriate soaking time contributes to the formation and development of {111} oriented grains, with the promoting effect of austenite transformation exceeding that of ferrite recrystallization. These findings provide insights into the microstructural characteristics and mechanical behaviors of the steel.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2021)
Article
Materials Science, Multidisciplinary
Seong Hoon Kim, Ji Hoon Kim, Jae Hoon Lee, Dong-Woo Suh, Jae Sang Lee
Summary: The present study investigates the phase constitution of a medium-carbon Q&P steel by comparing various approaches to the transformation stasis of bainitic ferrite and finds that the modified GEB approach can predict the phase constitution most accurately.
METALS AND MATERIALS INTERNATIONAL
(2022)
Article
Materials Science, Multidisciplinary
Xu Xie, Ming Zhong, Imants Kaldre, Zhiguo Qu, Dongming Wang, Cong Wang
Summary: The microstructural evolution roadmap in the weld metal of EH420 shipbuilding steel under different reheating inputs has been studied. As the reheating inputs increase, the major microstructures change from lath bainites to granular bainites, then to acicular ferrite, and finally to polygonal ferrite. The frequency of high-angle grain boundaries increases from 30 to 57.7 pct as reheating inputs increase from 50 to 150 kJ/cm, but a changeover occurs at 200 kJ/cm, leading to a significant reduction to 45.5 pct.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
Chunyuan Cui, Guangming Cao, Qiming Jiang, Kaifeng Xue, Zhenyu Liu
Summary: In this paper, a generalized additivity model is proposed to better describe anisothermal phase transformation kinetics. Machine learning is used to determine the kinetic parameters and compare them with experimental results. The effect of thermal path on anisothermal kinetics is also discussed.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
Zhenqiang Wang, Jiandong Wang, Haokai Dong, Yanyuan Zhou, Fengchun Jiang
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2020)
Article
Materials Science, Multidisciplinary
Haokai Dong, Yongjie Zhang, Goro Miyamoto, Masahiro Inomoto, Hao Chen, Zhigang Yang, Tadashi Furuhara
Summary: This study quantitatively investigated the amount of Nb segregation, energy dissipation, NbC precipitates, and interface velocity in Fe-0.08C-(0.035, 0.061)Nb model alloys. Results showed that energy dissipation at the migrating interface decreased with longer holding time or higher transformation temperature, and Nb atoms preferred to segregate at the non K-S interface. The occurrence of NbC interphase precipitation indirectly affected transformation kinetics by weakening the SDE via consumption of Nb solutes in ferrite.
Article
Materials Science, Multidisciplinary
Haokai Dong, Hao Chen, Ahmadreza Riyahi Khorasgani, Boning Zhang, Yongjie Zhang, Zhenqiang Wang, Xiaosheng Zhou, Wei Wang, Huanrong Wang, Tong Li, Zhigang Yang, Sybrand van der Zwaag
Summary: Molybdenum (Mo) is commonly used as an effective microalloying element in interphase precipitation steels to improve mechanical performance. However, the specific role of Mo in interphase precipitation behavior is not fully understood. Research has shown that in Mo-containing alloys, (Ti, Mo)C precipitates form instead of TiC, and the average site fraction of Mo in (Ti, Mo)C is independent of the bulk Mo content. Additionally, the number density of interphase precipitates can be significantly enhanced by a minor addition of Mo, with the Mo fraction in (Ti, Mo)C governing the driving force for precipitation nucleation and the interfacial energy of the interfaces.
Review
Materials Science, Multidisciplinary
Y. -J. Zhang, E. Chandiran, H. -K. Dong, N. Kamikawa, G. Miyamoto, T. Furuhara
Summary: This paper critically reviews the microstructural features and mechanical properties of micro-alloyed low carbon steels strengthened by interphase precipitation of nano-sized alloy carbides. Experimental results show that interphase precipitation significantly increases the strength of steels and maintains good ductility. By adjusting transformation conditions and chemical compositions, the driving force and dispersion of interphase precipitation can be refined.
Article
Metallurgy & Metallurgical Engineering
Yanyuan Zhou, Zhenqiang Wang, Haokai Dong, Fengchun Jiang
Summary: This study investigated the carbide precipitation at 925 degrees C in austenite of a low-carbon steel using experimental techniques and first-principles calculations. It was found that ultrafine W- and Fe-rich carbides form initially, followed by the nucleation and growth of Ti-rich (Ti, W)C particles with a core-shell structure. The composition and structure of carbides are influenced by a combined effect of W, Fe, and Ti atoms along with interstitial vacancies.
ACTA METALLURGICA SINICA-ENGLISH LETTERS
(2022)
Article
Metallurgy & Metallurgical Engineering
Junwei Xie, Haokai Dong, Yuxiu Hao, Zhongding Fan, Chang-An Wang
Summary: Experimental studies were conducted on deformation twins initiated in CryMnFeCoNi high entropy alloy at cryogenic temperature. It was found that under external loading, a three-dimensional shear stress concentration originating from dislocation tangling at both the grain boundaries and twin boundaries could be formed, promoting emission of partial dislocations from the planar defects and thus considered to be the key factor for twin formation. A sympathetic nucleation mechanism was proposed to describe the nucleation behaviors of twins.
ACTA METALLURGICA SINICA-ENGLISH LETTERS
(2022)
Article
Chemistry, Physical
Xiaosheng Zhou, Haokai Dong, Yushuai Wang, Meini Yuan
Summary: In this study, a Fe-Cr-Ni-Al-Ti ferritic superalloy was fabricated by hot isostatic pressing (HIP) and the types and evolution of precipitates were investigated. The results showed that the precipitates could be completely dissolved during solution treatment at 1100 degrees C, while they underwent morphological evolution and coalescence after aging at 700 degrees C. The alloy exhibited high tensile strength and elongation, but failure may occur at the initiation of cracks.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
Haokai Dong, Rui Zhong, Lehua Liu, Zhi Wang, Chao Yang, Zongqiang Luo, Weiwen Zhang
Summary: This study investigates the precipitation behavior of intergranular G phase in a cast Cu-17Ni-3Al based complex alloy. The results show that the G phases have a composition close to Ni16Ti6Si7 but with the incorporation of Zr and minor Cr. They tend to precipitate at high-angle grain boundaries adjacent to intergranular oxides and hold a rational orientation relationship with the Cu matrix. The substitution of Ti by Zr in G phase is energetically favorable, reducing the lattice misfit of the G phase/matrix interface.
MATERIALS CHARACTERIZATION
(2023)
Article
Nanoscience & Nanotechnology
Shichun Liu, Haokai Dong, Yubo Li, Zhigang Yang, Hao Chen
Summary: This study explores the potential effects of flash annealing on the microstructure and mechanical properties of cold-rolled NANOHITEN ferritic steel. The process results in an ultrafine-grained heterostructured matrix, composed of recrystallized/transformed and non-recrystallized/transformed domains, leading to a high strength level of 1 GPa without significant loss in ductility.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Nanoscience & Nanotechnology
Haokai Dong, Yongjie Zhang, Goro Miyamoto, Masahiro Inomoto, Weiwen Zhang, Lehua Liu, Hao Chen, Tadashi Furuhara
Summary: This study investigates the segregation behaviors of niobium at the migrating ferrite/austenite interface with ledge structure. It is found that, for the incoherent interface, niobium atoms segregate at the less mobile terrace. The experimental measurements are well explained by theoretical calculations based on solute drag theory.
SCRIPTA MATERIALIA
(2023)
Editorial Material
Chemistry, Physical
Haokai Dong, Haizhou Lu, Chao Zhao, Lehua Liu
Article
Materials Science, Multidisciplinary
J. T. Zhai, W. J. Gao, H. K. Dong, Yuan-Chao Hu, T. Zhang, X. G. Zhu, W. W. Zhang, C. Yang, L. H. Liu
Summary: This study presents a new method of reinforcing metals using a three-dimensional metallic glass lattice. The results show that composites reinforced with metallic glass possess excellent mechanical properties, with higher plasticity compared to other types of composites. The enhanced performances are attributed to the well-designed structure and the interaction between metallic glass and stainless steel.
APPLIED MATERIALS TODAY
(2022)
Article
Nanoscience & Nanotechnology
Haokai Dong, Yongjie Zhang, Goro Miyamoto, Hao Chen, Zhigang Yang, Tadashi Furuhara
SCRIPTA MATERIALIA
(2020)
Review
Materials Science, Multidisciplinary
Yang Ze-nan, Li Sai, Yu Jun-jie, Xie Qiang, Wang Zhen, Zhang Ming-da, Dong Hao-kai, Zhang Qiang, Yang Zhi-gang
CAILIAO GONGCHENG-JOURNAL OF MATERIALS ENGINEERING
(2020)
