Article
Materials Science, Multidisciplinary
Yandong Jing, Xuewei Fang, Naiyuan Xi, Xianlu Feng, Ke Huang
Summary: The study on the effect of laser shock peening (LSP) on 7050 aluminum alloy and 316L stainless steel revealed that no grain refinement was observed regardless of the laser cycles and energy density, but there was an increase in dislocation density. Tensile tests showed that the yield strength of both materials was improved after the LSP process, albeit sacrificing elongations. A potential method to calculate the dynamic yield stress of metallic materials was proposed with the help of the LSP process.
MATERIALS CHARACTERIZATION
(2021)
Article
Optics
Jiangdong Cao, Xueyu Cao, Bochen Jiang, Fang Yuan, Da Yao, Jian Huang
Summary: The study found that high power laser shock processing induced microstructural evolution in the Ni-based superalloy GH202, including dislocation slip and twinning. LSP also promoted dynamic recrystallization and the formation of dislocation arrays and subgrains within 250 microns in depth. Beyond 200 microns, the dislocation density significantly decreased.
OPTICS AND LASER TECHNOLOGY
(2021)
Article
Chemistry, Multidisciplinary
Qingsong Pan, Song Guo, Fang Cui, Lijun Jing, Lei Lu
Summary: Materials with designed gradient nanograins show exceptional mechanical properties, such as superior strength and ductility. This study demonstrates that a heterostructured 304 stainless steel with solely gradient dislocation structure (GDS) exhibits substantially improved yield strength with slightly reduced uniform elongation compared to its coarse grained counterparts. Microstructural observations reveal that multiple deformation mechanisms, including the formation of dense dislocation patterns, deformation twins and martensitic phase, contribute to the delocalized plastic deformation and superior mechanical performance of the GDS 304 stainless steel.
Article
Materials Science, Multidisciplinary
Wei Jiang, Yang Cao, Yingda Jiang, Yanfang Liu, Qingzhong Mao, Hao Zhou, Xiaozhou Liao, Yonghao Zhao
Summary: By high-pressure torsion processing, an austenitic stainless steel forms a hierarchical nanostructure with double the hardness value compared to the coarse-grained counterpart, which can be maintained at temperatures up to 600 degrees Celsius. Annealing treatment at temperatures from 400 to 600 degrees Celsius can induce recovery of the hierarchical nanostructure, reducing microstructural heterogeneity and increasing hardness.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2021)
Article
Engineering, Mechanical
L. M. Zhang, Z. X. Li, J. X. Hu, A. L. Ma, S. Zhang, E. F. Daniel, A. J. Umoh, H. X. Hu, Y. G. Zheng
Summary: The formation of martensite was found to initially increase and then decrease in 304 SS, affecting its resistance to ductile fracture and plastic deformation capability. While martensite was beneficial for enhancing CE resistance in the incubation and rising periods, it had a negative impact on plastic deformation ability in the stable period.
TRIBOLOGY INTERNATIONAL
(2021)
Article
Materials Science, Multidisciplinary
Guosheng Sun, Miaomiao Zhao, Linxiu Du, Hongyan Wu
Summary: The grain size of a 304 austenitic stainless steel was tuned through deformation-induced martensite transformation and austenite reversion annealing, and the effects of grain size on mechanical properties and deformation mechanisms were studied. Grain refinement significantly increased yield strength and elongation, while enhancing martensitic transformation. The formation of carbide precipitation and the change of martensite nucleation sites were attributed to the effects of grain size.
MATERIALS CHARACTERIZATION
(2022)
Article
Materials Science, Multidisciplinary
Junheng Gao, Suihe Jiang, Haitao Zhao, Yuhe Huang, Huairuo Zhang, Shuize Wang, Guilin Wu, Yuan Wu, Honghui Wu, Albert Davydov, William Mark Rainforth, Zhaoping Lu, Xinping Mao
Summary: By massive nano-precipitation, the grain sizes of a near medium Mn austenitic steel were successfully refined, leading to a transition of deformation mechanism and achieving a unique combination of high strength and large elongation.
Article
Materials Science, Multidisciplinary
Megumi Kawasaki, Jae-Kyung Han, Xiaojing Liu, Yusuke Onuki, Yulia O. Kuzminova, Stanislav A. Evlashin, Alexander M. Pesin, Alexander P. Zhilyaev, Klaus-Dieter Liss
Summary: Lab-scale X-ray diffraction and in situ heating neutron diffraction were conducted to evaluate structural changes in an additive-manufactured (AM) 316L stainless steel. The study found sequential structural relaxation and linear thermal lattice expansion in the nanostructured AM steel during heating, and observed different relaxation behaviors based on changes in crystallite sizes and dislocation densities. Furthermore, the manuscript connects critical subjects in materials science of advanced manufacturing, metal processing, and properties with novel time-resolved characterization techniques.
ADVANCED ENGINEERING MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Y. Xing, C. J. Li, Y. K. Mu, Y. D. Jia, K. K. Song, J. Tan, G. Wang, Z. Q. Zhang, J. H. Yi, J. Eckert
Summary: A multiphase CrMnFeCoNi high-entropy alloy (HEA) material was successfully prepared using a powder metallurgy process, and the critical roles of nanoscale particle formation and deformation twinning in the strain hardening ability of the material were revealed through microstructural characterization and mechanical testing.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Automation & Control Systems
Zhuangzhuang Hou, Shichao Xiu, Cong Sun, Yuan Hong, Xiannan Zou, Yunlong Yao
Summary: The grain refinement behaviors of stainless steel materials under pre-stress grinding (PG) were studied using a 3D FE-CA coupling method and experimental comparisons. The qualitative agreement with experiments was good. The visual tracking of recrystallized grain evolution during PG revealed distinct stages, including nucleation, nucleus blooming, grain coarsening, and stable size stages. The study also found that the acquisition of dynamic recrystallization on the ground surface requires aggressive grinding parameters and pre-stress in PG.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2023)
Article
Engineering, Mechanical
Wei Li, Huitao Chen, Weiying Huang, Jian Chen, Lu Zuo, Cong Li, Jianjun He, Yanjie Ren, Shengde Zhang
Summary: The enhanced fatigue property of aluminized stainless steel was achieved by the high fraction twinning and compressive residual stress induced by LSP treatment, with detwinning conspicuously noticed in LSP samples and dynamic recovery only observed at the severe plastic deformation layer during cyclic deformation related to CRS.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Nanoscience & Nanotechnology
Hiromi Miura, Chihiro Watanabe, Yoshiteru Aoyagi, Yojiro Oba, Masakazu Kobayashi, Naoki Yoshinaga
Summary: A stable SUS316LN austenitic stainless steel was cold-rolled to 92% reduction to form a complicated heterogeneous nanostructure. The material showed high tensile strength along the transverse direction, and peak aging further increased the strength. Grain-boundary segregation and the nano-lamellar structure contributed to the high strengthening effect.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Seong-Woo Choi, Jae Suk Jeong, Jong Woo Won, Jae Keun Hong, Yoon Suk Choi
Summary: Cryogenic-temperature rolling (CTR) significantly increases the yield strength of commercially pure titanium, demonstrating twinning-induced grain refinement and dislocation accumulation as the main mechanisms for strengthening. This method provides a way to achieve ultrahigh-strength CP titanium for structural applications requiring high-strength materials.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2021)
Article
Optics
Lei Guan, Zexin Ye, Jiaxin Zhong, Yu Li, Yongkang Zhang
Summary: This study investigates the effects of laser shock peening (LSP) on the pitting corrosion behavior of austenite stainless steel in an acid chloride environment. The results show that LSP treatment improves the pitting corrosion resistance of 304L stainless steel, resulting in a higher pitting potential and a lower metastable pitting nucleation rate of larger pits. However, this augmented effect is only significant in the case of massive LSP impacts.
OPTICS AND LASER TECHNOLOGY
(2022)
Article
Materials Science, Multidisciplinary
Baisong Cheng, Fengxia Wei, Wei Hock Teh, Kok Heng Cheong, Jing Jun Lee, Li Tian Chew, Kwang Boon Lau, Tang Hieu Binh Ma, Chee Koon Ng, Pei Wang, Upadrasta Ramamurty, Cheng Cheh Tan
Summary: Hadfield steel (HS) containing 0.83 wt% carbon was manufactured using laser powder bed fusion (LPBF) with mixed Fe-Mn, pure-Fe, and Fe-C powders. The LPBF HS has superior strength and hardness compared to conventionally fabricated HS, due to the refinement in grain size and increase in dislocation density caused by rapid solidification during LPBF. Carbide formation is prevented, and the main alloying elements are retained in solution.
MATERIALS & DESIGN
(2023)
Article
Optics
Chuanyu Wang, Jianzhong Zhou, Teng Zhang, Xiankai Meng, Pengfei Li, Shu Huang
Summary: This paper establishes a three-dimensional numerical model to investigate the non-isothermal flow and solidification characteristics in laser cladding process. Through theoretical analysis and simulation, the variations of temperature and solidification rate on the solidification front are revealed, and the reliability of the model is verified by comparing with experimental measurements.
OPTICS AND LASER TECHNOLOGY
(2022)
Article
Chemistry, Physical
Qi Sun, Jianzhong Zhou, Pengfei Li
Summary: This study analyzes the deformations, errors, and surface quality of micro milling process of aluminum alloy Al6061. The results from simulations and experiments demonstrate that the vertical stiffness of thin-walled structures and cutting force are the main factors causing deformation, and the poor quality area, top burr, and concave defects on the surface directly affect the machining quality. Future work should focus on improving surface quality, reducing surface defects, and increasing the stiffness at the top of thin-walled structures.
Article
Engineering, Manufacturing
Li Li, Xiankai Meng, Shu Huang, Hui Wang, Pengfei Li, Jianzhong Zhou
Summary: The experimental results demonstrate that reducing the scanning speed can increase the microhardness and tensile strength of the Al-Li alloy samples, reduce metallurgical defects, and improve the overall properties of the material.
JOURNAL OF MANUFACTURING PROCESSES
(2022)
Article
Materials Science, Ceramics
G. Q. Jiang, J. Z. Zhou, Z. W. Jiang, T. Zhang, L. Li, Y. Q. Gou, H. Zhang, C. Y. Cui, S. Huang, X. K. Meng
Summary: The microstructure of (Nb,Ta)C/Ni composite cladding coatings was modified by laser shock peening, which effectively enhanced the corrosion resistance of the coatings. The coupling effect of fine grains and compressive stress induced by laser shock waves inhibited corrosion propagation. Correspondence between corrosion morphology and microstructure was established, and interdiffusion phenomenon existed between (Nb,Ta)C and Fe-Ni alloy.
CERAMICS INTERNATIONAL
(2023)
Article
Materials Science, Multidisciplinary
Jing Liu, Pengfei Li, Yanyan Huai, Yadong Gong, Jianzhong Zhou, Jinzhong Lu
Summary: Laminated composites of IN718-95% IN718 + 5% (Cr2O3 + 25% TiO2) were fabricated using directed energy deposition and different posttreatment methods were applied. The interfacial microstructures and mechanical properties of the laminated composites were studied, and it was found that the precipitated strengthening phases improved the microhardness of the solution through double aging and homogenization treatment.
JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE
(2023)
Article
Materials Science, Multidisciplinary
Jiale Xu, Zengrong Hu, Songtao Wang, Wensheng Tan, Jianzhong Zhou
Summary: Laser cladded Co-based coatings with electromagnetic/ultrasonic compound energy field exhibit improved wear resistance and microstructural uniformity.
MATERIALS SCIENCE AND TECHNOLOGY
(2023)
Article
Engineering, Manufacturing
Hao Zhu, Zixuan Jiang, Jincai Han, Viboon Saetang, Kun Xu, Yang Liu, Zhaoyang Zhang, Shu Huang, Jianzhong Zhou
Summary: The efficiency and precision of electrochemical machining (ECM) of germanium (Ge) wafer can be significantly improved by introducing laser irradiation. A NaNO3 electrolyte jet is formed via a cathodic nozzle and impacts perpendicularly on the bottom of the Ge wafer, while nanosecond laser irradiates from opposing side to enhance electrical conductivity locally. This method allows for the fabrication of dimple structures without any detectable oxidation products. Surface morphology characterization shows radial lines consisting of regular micro-waving structure and irregular corrugated patterns near the dimple edge and center, respectively.
JOURNAL OF MANUFACTURING PROCESSES
(2023)
Article
Materials Science, Multidisciplinary
Jizhuang Wang, Jianzhong Zhou, Teng Zhang, Xiankai Meng, Pengfei Li, Shu Huang, Hao Zhu
Summary: Laser cladding was used to prepare three composite coatings: Inconel 718, IN718-50 wt.% WC, and IN718-50 wt.% WC with ultrasonic vibration. Adding WC increased hardness and improved tribological properties, but also caused aggregation and carbides formation with rough structure. Ultrasonic vibration refined the microstructure and reduced aggregation, resulting in increased microhardness and lower COF. WC particles and refined carbides converted wear mechanism and increased residual stress. Acoustic cavitation mainly occurred in the middle and bottom of the molten pool, and proper frequency ultrasonic facilitated cavitation effect.
Article
Engineering, Mechanical
Xiankai Meng, Xumin Leng, Chong Shan, Liucheng Zhou, Jianzhong Zhou, Shu Huang, Jinzhong Lu
Summary: In this study, ultrasonic-assisted laser shock peening (ULP) was proposed to improve the fatigue resistance of 2024-T351 aluminum alloys by combining ultrasonic shock peening (UP) and laser shock peening (LP) techniques to enhance the microstructure and mechanical properties. The microstructure, residual stress, microhardness, and vibration fatigue life of four different specimen types were tested and analyzed. The results showed that ULP significantly increased the dislocation density and refined the grains, leading to higher compressive residual stress and microhardness, which inhibited crack initiation and propagation, and thus greatly increased the vibration fatigue life.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Chemistry, Physical
Guang-lei Liu, Wen-chao Xue, Yu-hao Cao, Xiao-xuan Sun, Zhi-qiang Li, Fu-hai Xu, Hai-xia Liu, Jian-zhong Zhou
Summary: This study investigates the effects of laser shock processing (LSP) on the thermal fatigue life and crack growth behavior of the coating and bonding area of the brake disc. The results show that LSP can enhance the thermal fatigue performance of the brake disc repaired by laser cladding.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
Guanglei Liu, Wenchao Xue, Yuhao Cao, Zhiqiang Li, Xiaoxuan Sun, Fuhai Xu, Haixia Liu, Jianzhong Zhou
Summary: The effects of Laser Shock Peening (LSP) on the microhardness, residual stress, and microstructure of the Ni60 cladding layer and the combined area of the 20CrNiMo alloy were investigated. The results show that LSP can improve the microhardness, introduce residual compressive stress, and refine the microstructure. The residual compressive stress value is -538 MPa on the surface and -30 MPa at a depth of 2 mm.
JOURNAL OF LASER APPLICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Qi Sun, Jianzhong Zhou, Xiankai Meng, Pengfei Li
Summary: The mechanical properties and microstructure characteristics of 2024-T351 aluminum alloy after paint removal by laser cleaning were investigated. Surface microhardness and tensile strength of the samples were measured before and after laser cleaning. It was found that laser cleaning increased the surface microhardness by 10.6% and tensile strength by 8.4%. The enhancement was attributed to grain refinement and dislocation proliferation induced during the laser cleaning process.
Article
Engineering, Manufacturing
Pengfei Li, Qingtao Yang, Liangliang Li, Yadong Gong, Jianzhong Zhou, Jinzhong Lu
Summary: In situ synthesis of ceramic-reinforced 316L/IN718 matrix composites by directed energy deposition has been achieved successfully. The microstructure, microhardness, tensile properties, and wear resistance of metal matrix composites were compared with those of unreinforced samples. The results show that the addition of Ti powder significantly enhances the microhardness and wear resistance, making it a practical and cost-effective approach for preparing high-strength and wear-resistant materials.
JOURNAL OF MANUFACTURING PROCESSES
(2023)
Article
Materials Science, Multidisciplinary
Pengfei Li, Yuhang Wang, Liangliang Li, Yadong Gong, Jianzhong Zhou, Jinzhong Lu
Summary: In this study, nanosecond pulse lasers were used to polish the surface of TA15 titanium alloy and the effects on surface morphology, microstructure evolution, oxidation depth, and mechanical properties were investigated. The results showed that both high-power and low-power lasers effectively reduced the surface roughness, but the low-power laser had a better polishing effect and resulted in a smaller oxidation depth.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Materials Science, Multidisciplinary
Yixin Wang, Jianzhong Zhou, Teng Zhang, Pengfei Li, Hao Zhu, Xiankai Meng
Summary: A novel numerical model was proposed to simulate the solidification process of IN718/WC composite coatings using the coupled multi-phase-field model and lattice Boltzmann method. Different microstructures around WC particles were successfully simulated and verified by experiments. The results show that WC convection diffusion bands can inhibit the growth of columnar crystals, increasing the hardness and wear resistance of the coating.
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.
