Article
Green & Sustainable Science & Technology
L. Deconinck, T. Depover, K. Verbeken
Summary: The present study experimentally investigates the uptake of hydrogen and the formation of hydrides in duplex Ti-6Al-4V. Hydrogen is introduced through electrochemical charging at room temperature. The effects of charging duration and current density are evaluated, revealing lattice strains and the formation of titanium hydrides under severe charging conditions. The charging conditions significantly influence the hydrogen distribution and hydride formation in the material. Controlling the electrochemical hydrogen charging conditions provides a better understanding of hydrogen-induced failure mechanisms and offers opportunities for sustainable thermohydrogen processing of titanium.
MATERIALS TODAY SUSTAINABILITY
(2023)
Article
Materials Science, Multidisciplinary
Xinyu Yang, Richard A. Barrett, Noel M. Harrison, Sean B. Leen
Summary: A physically-based, mixed-phase structure-property model is developed for analyzing the microstructure-sensitivity of tensile stress-strain response in additively manufactured Ti-6Al-4V, considering the effects of solutes, grain size, phase volume fraction, and dislocation density. The model incorporates solid-state phase transformation and dislocation density evolution to simulate the effects of martensite dissolution and a -b transformation at high temperature, allowing for rapid process-structure-property prediction and optimization.
MATERIALS & DESIGN
(2021)
Article
Chemistry, Physical
Yujian Wang, Junjie Li, Jianwei Li, Lei Zhang, Jiankai Ma, Zhijun Wang, Feng He, Jincheng Wang
Summary: Coarsening of the basketweave alpha + beta microstructure in Ti-6Al-4V during thermal cycling is driven by multiple dissolution and precipitation transformations instead of conventional Ostwald ripening. This study reveals that the vanishing of alpha plates continues during repeated thermal cycling through two mechanisms, which are related to the Gibbs-Thomson effect. The influence of cycling frequency and total duration on the coarsening transformation is also detected. Long cycling duration leads to severe coarsening, while the final coarsening of alpha plates is almost independent of the cycling frequency.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
Matteo Villa, Jeffery W. Brooks, Richard Turner, Frederic Boitout, Robin Mark Ward
Summary: This study examined the microstructure evolution of Ti-6Al-4V titanium alloy during high energy density welding process through numerical simulations and experimental validations. The numerical predictions were shown to reasonably match with experimental results, validating various metallurgical features of the alloy.
Article
Materials Science, Multidisciplinary
Dingcong Cui, Yashan Zhang, Feng He, Jiankai Ma, Kaiwei Zhang, Zhongsheng Yang, Junjie Li, Zhijun Wang, Ji-jung Kai, Jincheng Wang, Feng Jun
Summary: Preheating is an effective method to customize the heterogeneous microstructure in the bonding zone of HMed Ti-6Al-4V by influencing the cooling rate and pseudo-isothermal annealing temperature.
MATERIALS RESEARCH LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Lai Wei, Xiaofeng Xu, Yang Zhao, Yachong Zhou, Xudong Yan, Zhicheng Wu, Yongqiang Yu, Chao Wu
Summary: In this study, a shortened process combining electropulsing treatment and conventional heat treatment has been applied to develop a tri-modal microstructure in Ti-6Al-4V alloy. The tri-modal microstructure has good overall mechanical properties. It was found that electropulsing treatment contributes to the formation of low aspect ratio martensite, while the conventional heat treatment retains this morphology in the alpha grains, which can be easily spheroidized.
MATERIALS CHARACTERIZATION
(2023)
Article
Materials Science, Multidisciplinary
J. R. Kennedy, A. E. Davis, A. E. Caballero, M. White, J. Fellowes, E. J. Pickering, P. B. Prangnell
Summary: The nature of chemical mixing and microstructure gradients across interface transitions in manufacturing tailored components with two high-performance dissimilar titanium alloys using the wire-arc additive manufacturing process has been explored. The study found that a relatively long-range chemical gradient occurs during the transition between layers produced with the two different titanium alloys, leading to a stepwise exponential decay composition profile. The alloy-alloy composition gradients had little effect on the grain structure but strongly influenced the transformation microstructure.
MATERIALS CHARACTERIZATION
(2021)
Article
Materials Science, Multidisciplinary
Jinlong Su, Fulin Jiang, Junjie Li, Chaolin Tan, Zili Xu, Haiming Xie, Jin Liu, Jie Tang, Dingfa Fu, Hui Zhang, Jie Teng
Summary: Understanding the phase transformation behaviors and microstructural evolutions during post-heat treatments is crucial for improving the mechanical performances of additively manufactured titanium alloys. This study investigates the effects of distinctive dual-stage heat treatments on the Ti-6Al-4V alloy and demonstrates that the combination of dual-stage heat treatments and salt bath quenching is an effective approach for obtaining fine microstructures and optimized strength and ductility. The study also discusses the influence of phase transformation behaviors and dislocation types on the microstructure and strengthening of the alloy.
MATERIALS & DESIGN
(2022)
Article
Materials Science, Multidisciplinary
A. E. Davis, J. Donoghue, J. R. Kennedy, N. Byres, P. B. Prangnell
Summary: In-situ cooling experiments were conducted on Ti64 samples for the first time, revealing the development of alpha colonies. Primary alpha laths play a crucial role in influencing subsequent colony growth and transformation process by nucleating secondary alpha laths through sympathetic autocatalysis.
Article
Chemistry, Physical
Xiaofeng Xu, Xudong Yan, Yu Qian, Xueying Chong, Yachong Zhou, Yuguang Zhao, Xuehui Yang, Gaofeng Liu, Chao Wu
Summary: In this study, a high-strength and properly ductile Ti-6Al-4V alloy was successfully prepared using an innovative strategy based on electropulsing. The unique microstructure evolution resulting from electropulsing led to efficient alpha' lath refinement, which greatly enhanced the strength of the alloy. This novel bi-lamellar microstructure also contributed to the proper ductility of the alloy. These results and analysis offer a new approach to improving and controlling the mechanical properties of Titanium alloys.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Physics, Applied
Xiaohong Zhan, Chaoqi Qi, Mengyao Wu, Lijun Liu, Zhuanni Gao
Summary: High-entropy alloys (HEAs) show great promise in terms of comprehensive properties, with an equiatomic FeCoCrNi HEA used for laser cladding on Ti-6Al-4V alloy in this study. Characterization of the HEA coating reveals a mixture of FCC and BCC phases, with small amounts of (Fe, Cr)-rich and (Ni, Ti)-rich phases. The bonding region is formed by convection resulting from density differences between HEA and TC4, with convection in the molten pool playing a key role in the morphology of the bonding region.
MODERN PHYSICS LETTERS B
(2021)
Article
Nanoscience & Nanotechnology
Harish Chandra Kaushik, Mahdi Habibnejad Korayem, Amir Hadadzadeh
Summary: This study investigates the kinetics of phase transformation in L-PBF titanium alloys using differential scanning calorimetry (DSC). Both non-isothermal and isothermal kinetics models were developed, and the effects of alloying elements and initial microstructure on the transformation kinetics were discussed. The results provide insights into the design of heat treatments to achieve desired microstructures and properties in L-PBF titanium alloys.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Weizhao Sun, Feihu Shan, Nanfu Zong, Hongbiao Dong, Tao Jing
Summary: This research investigates the phase transformation of Ti-6Al-4V during wire laser additive manufacturing using a density-based constituent phase simulation method. By increasing temperature and decreasing cooling rate, the undesirable alpha' phase can be narrowed or even eliminated. Additionally, the laser power of 3000 W results in more transformed alpha(B) without increasing alpha-lath thickness compared to the 2500 W case. The simulation shows promising prospects in predicting phase transformation and optimizing processing parameters.
MATERIALS & DESIGN
(2021)
Article
Materials Science, Multidisciplinary
Lara Draelos-Hagerty, James D. Paramore, Brady G. Butler, Peeyush Nandwana, Ankit Srivastava
Summary: This article presents a thermohydrogen post-process treatment that can achieve equiaxed grain morphology in EBM-processed Ti-6Al-4V without sacrificing mechanical properties.
METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
Venkata Satya Surya Amaranth Karra, Amit K. Verma, Ali Guzel, Andrew Huck, Anthony D. Rollett
Summary: This study presents a methodology for quantifying basketweave Ti-6Al-4V microstructures, focusing on automated quantification of features such as alpha lamella thickness and volume fractions of both alpha and beta phases. The results were compared with a commercial software package that uses a similar methodology. The methodology is expected to be applicable to other microstructure types via adaptation.
MATERIALS CHARACTERIZATION
(2022)
Article
Materials Science, Multidisciplinary
Y. Liu, K. Zweiacker, C. Liu, J. T. McKeown, J. M. K. Wiezorek
Summary: The evolution of rapid solidification microstructure and solidification interface velocity of hypereutectic Al-20at.%Cu alloy after laser melting has been studied experimentally. It was found that the formation of microstructure was dominated by eutectic, alpha-cell, and banded morphology grains, and the growth modes changed with increasing interface velocity.
Article
Materials Science, Multidisciplinary
Bharat Gwalani, Julian Escobar, Miao Song, Jonova Thomas, Joshua Silverstein, Andrew Chihpin Chuang, Dileep Singh, Michael P. Brady, Yukinori Yamamoto, Thomas R. Watkins, Arun Devaraj
Summary: Castable alumina forming austenitic alloys exhibit superior creep life and oxidation resistance at high temperatures. This study reveals the mechanism behind the enhanced creep performance of these alloys by suppressing primary carbide formation and offers a promising alloy design strategy for high-temperature applications.
Article
Materials Science, Multidisciplinary
Jian Song, Qi Zhang, Songsong Yao, Kunming Yang, Houyu Ma, Jiamiao Ni, Boan Zhong, Yue Liu, Jian Wang, Tongxiang Fan
Summary: Recent studies have shown that achieving an atomically flat surface for metals can greatly improve their oxidation resistance and enhance their electronic-optical applications. Researchers have explored the use of graphene as a covering layer to achieve atomically flat surfaces. They found that high-temperature deposited graphene on copper surfaces formed mono-atomic steps, while annealed copper and transferred graphene on copper interfaces formed multi-atomic steps.
Article
Materials Science, Multidisciplinary
Jennifer A. Glerum, Jon-Erik Mogonye, David C. Dunand
Summary: Elemental powders of Al, Ti, Sc, and Zr are blended and processed via laser powder-bed fusion to create binary and ternary alloys. The microstructural analysis and mechanical testing show that the addition of Ti results in the formation of primary precipitates, while the addition of Sc and Zr leads to the formation of fine grain bands. The Al-0.25Ti-0.25Zr alloy exhibits comparable strain rates to Al-0.5Zr at low stresses, but significantly higher strain rates at higher stresses during compressive creep testing. Finite element modeling suggests that the connectivity of coarse and fine grain regions is a critical factor affecting the creep resistance of the alloys.
Article
Materials Science, Multidisciplinary
P. Jannotti, B. C. Hornbuckle, J. T. Lloyd, N. Lorenzo, M. Aniska, T. L. Luckenbaugh, A. J. Roberts, A. Giri, K. A. Darling
Summary: This work characterizes the thermo-mechanical behavior of bulk nanocrystalline Cu-Ta alloys under extreme conditions. The experiments reveal that the alloys exhibit unique mechanical properties, behaving differently from conventional nanocrystalline Cu. They do not undergo grain coarsening during extrusion and exhibit behavior similar to coarse-grained Cu.
Article
Materials Science, Multidisciplinary
Yiqing Wei, Jingwei Li, Daliang Zhang, Bin Zhang, Zizhen Zhou, Guang Han, Guoyu Wang, Carmelo Prestipino, Pierric Lemoine, Emmanuel Guilmeau, Xu Lu, Xiaoyuan Zhou
Summary: This study proposes a new strategy to modify microstructure by phase regulation, which can simultaneously enhance carrier mobility and reduce lattice thermal conductivity. The addition of Cu in layered SnSe2 induces a phase transition that leads to increased grain size and reduced stacking fault density, resulting in improved carrier mobility and lower lattice thermal conductivity.
Article
Materials Science, Multidisciplinary
Jia Chen, Zhengyu Zhang, Eitan Hershkovitz, Jonathan Poplawsky, Raja Shekar Bhupal Dandu, Chang-Yu Hung, Wenbo Wang, Yi Yao, Lin Li, Hongliang Xin, Honggyu Kim, Wenjun Cai
Summary: In this study, the structural origin of the pH-dependent repassivation mechanisms in multi-principal element alloys (MPEA) was investigated using surface characterization and computational simulations. It was found that selective oxidation in acidic to neutral solutions leads to enhanced nickel enrichment on the surface, resulting in reduced repassivation capability and corrosion resistance.
Article
Materials Science, Multidisciplinary
X. Y. Xu, C. P. Huang, H. Y. Wang, Y. Z. Li, M. X. Huang
Summary: The limited slip systems of magnesium (Mg) and its alloys hinder their wide applications. By conducting tensile straining experiments, researchers discovered a rate-dependent transition in the dislocation mechanisms of Mg alloys. At high strain rates, glissile dislocations dominate, while easy-glide dislocations dominate at low strain rates. Abundant glissile dislocations do not necessarily improve ductility.
Article
Materials Science, Multidisciplinary
M. S. Szczerba, M. J. Szczerba
Summary: Inverse temperature dependences of the detwinning stress were observed in face-centered cubic deformation twins in Cu-8at.%Al alloy. The detwinning stress increased with temperature when the pi detwinning mode was involved, but decreased when the pi/3 mode was involved. The dual effect of temperature on the detwinning stress was due to the reduction of internal stresses pre-existing within the deformation twins. The complete reduction of internal stresses at about 530 degrees C led to the equivalence of the critical stresses of different detwinning modes and a decrease in the yield stress anisotropy of the twin/matrix structure.
Article
Materials Science, Multidisciplinary
Taowen Dong, Tingting Qin, Wei Zhang, Yaowen Zhang, Zhuoran Feng, Yuxiang Gao, Zhongyu Pan, Zixiang Xia, Yan Wang, Chunming Yang, Peng Wang, Weitao Zheng
Summary: The interaction between the electrode and the electric double layer (EDL) significantly influences the energy storage mechanism. By studying the popular alpha-Fe2O3 electrode and the EDL interaction, we find that the energy storage mechanism of the electrode can be controlled by modulating the EDL.
Article
Materials Science, Multidisciplinary
Matthew R. Barnett, Jun Wang, Sitarama R. Kada, Alban de Vaucorbeil, Andrew Stevenson, Marc Fivel, Peter A. Lynch
Summary: The elastic-plastic transition in magnesium alloy Mg-4.5Zn exhibits bursts of deformation, which are characterized by sudden changes in grain orientation. These bursts occur in a coordinated manner among nearby grains, with the highest burst rate observed at the onset of full plasticity. The most significant burst events are associated with twinning, supported by the observation of twinned structures using electron microscopy. The bursts are often preceded and followed by a stasis in peak movement, indicating a certain "birth size" for twins upon formation and subsequent growth at a later stage.
Article
Materials Science, Multidisciplinary
Vaidehi Menon, Sambit Das, Vikram Gavini, Liang Qi
Summary: Understanding solute segregation thermodynamics is crucial for investigating grain boundary properties. The spectral approach and thermodynamic integration methods can be used to predict solute segregation behavior at grain boundaries and compare with experimental observations, thus aiding in alloy design and performance control.
Article
Materials Science, Multidisciplinary
Feiyu Qin, Lei Hu, Yingcai Zhu, Yuki Sakai, Shogo Kawaguchi, Akihiko Machida, Tetsu Watanuki, Yue-Wen Fang, Jun Sun, Xiangdong Ding, Masaki Azuma
Summary: This study reports on the negative and zero thermal expansion properties of Cd2Re2O7 and Cd1.95Ni0.05Re2O7 materials, along with their ultra-low thermal conductivity. Through investigations of their structures and phonon calculations, the synergistic effect of local structure distortion and soft phonons is revealed as the key to achieving these distinctive properties.
Article
Materials Science, Multidisciplinary
Thomas Beerli, Christian C. Roth, Dirk Mohr
Summary: A novel testing system for miniature specimens is designed to characterize the plastic response of materials for which conventional full-size specimens cannot be extracted. The system has an automated operation process, which reduces the damage to specimens caused by manual handling and improves the stability of the test results. The experiments show that the miniature specimens extracted from stainless steel and aluminum have high reproducibility, and the results are consistent with those of conventional-sized specimens. A correction procedure is provided to consider the influence of surface roughness and heat-affected zone caused by wire EDM.
Article
Materials Science, Multidisciplinary
Rani Mary Joy, Paulius Pobedinskas, Nina Baule, Shengyuan Bai, Daen Jannis, Nicolas Gauquelin, Marie-Amandine Pinault-Thaury, Francois Jomard, Kamatchi Jothiramalingam Sankaran, Rozita Rouzbahani, Fernando Lloret, Derese Desta, Jan D'Haen, Johan Verbeeck, Michael Frank Becker, Ken Haenen
Summary: This study investigates the influence of film microstructure and composition on the Young's modulus and residual stress in nanocrystalline diamond thin films. The results provide insights into the mechanical properties and intrinsic stress sources of these films, and demonstrate the potential for producing high-quality nanocrystalline diamond films under certain conditions.