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Near-perfect replication on amorphous alloys through active force modulation based on machine learning/neural network parameter prediction

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 181-191页

作者： Senkuan Meng Zheng Wang Ruisong Zhu Ruijie Liu Jiang Ma Lina Hu Weihua Wang Key Laboratory for Liquid-Solid Structural Evolution and Processing of materials (Ministry of Education) School of Materials Science and Engineering Shandong University College of Mechatronics and Control Engineering Shenzhen University Songshan Lake materials Laboratory institute of Physics Chinese Academy of Sciences

As a microforming technique, micro/nano-structural replication possesses advantages of high precision and efficiency. With the remarkable superplasticity in the supercooled liquid region, amorphous alloys or metallic glasses(MGs) are regarded as ideal materials for miniature fabrication. However, due to the intrinsic metastable nature of supercooled liquids, the design of imprinting processes for MGs poses a challenge. In the past, process parameters have largely relied on trial-and-error *** this work, a low-frequency active force modulation system is employed to apply a stable, precise, and real-time feedback stress field for imprinting of MG samples. Low-frequency vibrations can facilitate the filling of microstructures on the template surface by reducing the effective viscosity of the supercooled liquid. With the dataset composed of orthogonal experiments, a machine learning strategy based on back-propagation(BP) neural networks was utilized to construct a 3D parameter space for temperature, stress, and time, and to predict the corresponding filling ratio. Furthermore, the optimal combination of imprinting process parameters was identified, and its filling ratio was experimentally validated to reach as high as 0.94. The near-perfect replication of microstructures confirms the superiority of the active force modulation system and the data-driven strategy of machine learning-assisted parameter design. At the same time, this one-step microforming process provides a new approach to addressing the accuracy-cost trade-off dilemma in precision manufacturing.

关键词： metallic glass amorphous alloy microforming imprinting machine learning

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An impregnation-reduction method to prepare graphite nanosheet/alumina composites and its high-frequency dielectric properties

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Rare Metals 2017年第3期36卷 205-208页

作者： Ke-Lan Yan Run-Hua Fan Min Chen Kai Sun Xu-Ai Wang Qing Hou Shi-Bing Pan Ming-Xun Yu Key Laboratory for Liquid-Solid Structural Evolution and Processing of materials(Ministry of Education) Shandong UniversityJinan 250061China shandong non-metallic materials Research institute Jinan 250031 China

he nano-graphite sheet/alumina composites were prepared in situ by a facile impregnation-reduction *** microstructure of the composites was analyzed by X-ray diffraction （XRD）,and the final phase composition after reduction is Al2O3,metal Fe and graphite *** electron microscopy （SEM） images show that the particle size of Fe is about 20 nm,and the lamellae thickness of the graphite is about 30 ***,the dielectric properties and conductive mechanism of the composites were investigated experimentally in the frequency range of 0.01-1.00 GHz by impedance *** results show that the real part of permittivity of composites increases with Fe3＋ concentration,which is due to the increase in interfacial polarization between Fe and A12O3 and the three-dimensional network of lamellar graphite ***,tunable microtopography and electrical parameters of nano-graphite sheet/alumina composites can be realized by changing Fe3＋ concentration.

关键词： Impregnation-reduction method Ceramicmatrix composites Graphite sheet Complex permittivity Conductivity

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STUDY OF THE STRESS INTENSITY FACTOR OF PREFORMED V SHAPE FRACTURE TIP

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Applied Mathematics and Mechanics(English Edition) 1992年第5期13卷 487-496页

作者：王成端 Department of non-metallic Minerals Sichuan Institute of Building Materials Mianyang

In order to make the fracture cross-section of rock smooth in controlled cutting-blast, generally, two V-shape-notches on the inner wall of a shot hole are notched in symmetry along the design direction. A V-shape notch approximately be considered as V-shape-fracture under certain condition. This paper gave the complex stress function of preformed V-shape-fracture under a blasting load. The stress field and displacement field at the tip of a preformed V-shape-fracture were derived with Westergaard's method, hence its stressintensity factor was obtained. To verify the derived results, blasting tests were made with concrete samples of 400mm×400mm×300mm, and all having, in the center, a drilled hole of 25mm in diameter and 200mm in height. The test result showed that the formulas derived are correct and effective.

关键词： V shape fracture complex stress function stress intensity factor

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Residual stress and precipitation of Mg-5Zn-3.5Sn-1Mn-0.5Ca-0.5Cu alloy with different quenching rates

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Journal of Magnesium and Alloys 2021年第2期9卷 604-612页

作者： Cong Wang Tianjiao Luo Yunteng Liu Qiuyan Huang Yuansheng Yang institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of materials Science and Engineering Northeastern UniversityShenyang 110819China shandong Key Laboratory for High Strength Lightweight metallic materials Advanced Materials InstituteShandong Academy of SciencesShandong 250014China

The effect of the quenching rate after solution treatment on the residual stress and precipitation behavior of a high strength Mg-5 Zn-3.5 Sn-1 Mn-0.5 Ca-0.5 Cu plate is *** simulation results show decreasing temperature gradient in the plate with decreasing quenching rate,which leads to weakened inhomogeneous plastic deformation and decreased residual *** dynamic precipitation on the grain boundary happens after either cold water cooling or air cooling,however,air cooling leads to dynamic precipitation of Mg-Zn phase on Mn particles around which a low-density precipitate zone develops after aging ***,the fine and densely distributed Mg-Zn precipitates observed after aging treatment of the cold water cooled alloy are replaced by coarse precipitates with low density for the air cooled *** the low-density precipitate zone near Mn particles and the coarsening of precipitates are the source of the decrease in hardness and tensile properties of the air cooled *** residual stress drops faster than the hardness with decreasing quenching rate,which makes it possible to lower the residual stress without sacrificing too much age-hardening ability of the alloy.

关键词： Mg-5Zn-3.5Sn-1Mn-0.5Ca-0.5Cu alloy Solution treatment Quenching rate Residual stress Precipitation Age-hardening

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Synthesis and Characteristic of a New Niobate:Ba_5NaCo_(0.5)Nb_(9.5)O_(30)

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Journal of Wuhan University of Technology(materials Science) 2001年第4期16卷 70-72页

作者：张高科 non-metallic Research institute Wuhan University of Technology Wuhan 430070 China

A new niobate crystal was synthesized for the first time in BaO-Na2O-Co2O3 -Nb2O5 system by solid state reaction and the flux method. The new compound was studied by X-ray diffraction, electron probe. N-ray microanalysis, chemical analysis and SEM. The result of the X-ray diffraction shows that Ba5 NaCo0.5 Nb9.5 OK) belongs to tetragonal tungsten bronze structure with space group P4bm( 100) and lattice parameters a = b = 12.4453(2) A, c = 3. 9770 (3) A and Z = 1. The structure of the compound is different from that ofBa4Na2Nb10O30

关键词： niobate cobalt tungsten bronze structure XRD

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A strategy to achieve efficient green-emission dual-mode luminescence of Yb^(3+),Er^(3+) doped NaBiF_(4)

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Rare Metals 2021年第8期40卷 2040-2048页

作者： Jin-Hui Xie Jue Wang Gui-Hua Qiu Xi-Bing Li Wen-Tao Huang Rui-Rong Zhang Tong Lin Li-Xi Wang Qi-Tu Zhang College of materials Science and Engineering Nanjing Tech UniversityNanjing210009China Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites Nanjing210009China shandong institute of non-metallic Material Jinan250031China

A series of hexagonal phase NaBiF_(4):x Yb^(3+),y Er^(3+) were successfully synthesized by solvothermal *** morphology,phase structure,up-conversion luminescence and down-conversion luminescence properties of Yb^(3+) and Er^(3+) doping concentration and the energy transfer mechanism were *** shows that the doping of Yb^(3+) and Er^(3+) does not cause the phase transition of NaBiF_(4),but influences its *** the NaBiF_(4):Yb^(3+),Er^(3+),Yb^(3+) can transfer energy with Er^(3+),enhancing up-conversion green *** Yb^(3+) doping concentration increasing,the up-conversion red-green ratio will increase while the down-conversion intensity of the green emission decreases and that of the red emission *** the potential application of Na BiF4:x Yb^(3+),y Er^(3+) phosphors in optical illumination,the thermal stability was carried out.

关键词： NaBiF_(4) Dual-mode luminescence Energy transfer High temperature fluorescence

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SYNTHESIS OF NEW BIOBATE CRYSTAL Ba_(2.6)Na_(0.4)Cu_(0.2)Nb_(4.8)O_(15)

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Journal of Wuhan University of Technology(materials Science) 2000年第4期15卷 57-60页

作者：张高科 non-metallic Research institute Wuhan University of Technology Wuhan 430070 China

New niobate crystal Ba_(2.6)Na_(0.4) Cu_(0.2)Nb_(4.8) O_15was synthesized in BaO-Na_2O-CuO-Nb_2O_5 system. Its morphology,optical properties, melting point and chem-ical stability were studied. X-ray power diffraction study determined that this compound is orthorhombic tung-sten bronze structure with space group Cmm^2 and Lattice parameters a=17.692(2),b=17. 684(2).c=3. 998(2). The new compound may be one kind of photorefractive crystals.

关键词： niobate tungsten bronze copper

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Review on field-induced phase transitions in lead-free NaNbO_(3)-based antiferroelectric perovskite oxides for energy storage

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Journal of Materiomics 2023年第1期9卷 1-18页

作者： Mao-Hua Zhang Lovro Fulanovi Changhao Zhao Jurij Koruza non-metallic Inorganic materials Department of Materials and Earth SciencesTechnical University of DarmstadtDarmstadt64287Germany institute for Chemistry and Technology of materials Graz University of TechnologyGraz8010Austria

Emerging new applications of antiferroelectric perovskite oxides based on their fascinating phase transformation between polar and nonpolar states have provided considerable attention to this class of materials even decades after the discovery of *** presenting the challenge of formulating a precise definition of antiferroelectric materials,we briefly summarize proposed *** the following,we focus on the crystallographic structures of the antiferroelectric and ferroelectric phases of NaNbO_(3),which is emerging as a promising alternative to PbZrO_(3)-based *** field-induced phase transition behavior of NaNbO_(3)-based AFE materials in the form of single crystals,bulk ceramics,and multilayer ceramic capacitors is *** advances in a group of materials exhibiting high energy storage performance and relaxor-like behavior are also *** influence of electrode geometry on phase transition behavior and thus on the energy storage property is briefly *** review concludes with an overview of the remaining challenges related to the fundamental understanding of the scientific richness of AFE materials in terms of structure,microstructure,defect transport under high fields,and phase transition dynamics required for their future development and applications.

关键词： Antiferroelectric Perovskite oxides Energy storage NaNbO_(3) Phase transition Lead free

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Characteristics of AZ31 Mg alloy joint using automatic TIG welding

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International Journal of Minerals,Metallurgy and materials 2017年第1期24卷 102-108页

作者： Hong-tao Liu Ji-xue Zhou Dong-qing Zhao Yun-teng Liu Jian-hua Wu Yuan-sheng Yang Bai-chang Ma Hai-hua Zhuang shandong Key Laboratory for High Strength Lightweight metallic materials Advanced Materials InstituteShandong Academy of SciencesJinan 250014China shandong Engineering Research Center for Lightweight Automobiles Magnesium Alloys Advanced Materials InstituteShandong Academy of SciencesJinan 250014China institute of Metal Research Chinese Academy of SciencesShenyang 110016China

The automatic tungsten-inert gas welding（ATIGW） of AZ31 Mg alloys was performed using a six-axis robot. The evolution of the microstructure and texture of the AZ31 auto-welded joints was studied by optical microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and electron backscatter diffraction. The ATIGW process resulted in coarse recrystallized grains in the heat affected zone（HAZ） and epitaxial growth of columnar grains in the fusion zone（FZ）. Substantial changes of texture between the base material（BM） and the FZ were detected. The {0002} basal plane in the BM was largely parallel to the sheet rolling plane, whereas the c-axis of the crystal lattice in the FZ inclined approximately 25° with respect to the welding direction. The maximum pole density increased from 9.45 in the BM to 12.9 in the FZ. The microhardness distribution, tensile properties, and fracture features of the AZ31 auto-welded joints were also investigated.

关键词： magnesium alloys TIG welding microstructure texture microhardness

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Crystal Structure of a New Compound:Na_(2.1)Ba_(0.9)Cu_(0.1)Nb_(4.9)O_(14.3)

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Journal of Wuhan University of Technology(materials Science) 2001年第1期16卷 30-33页

作者：张高科 non-metallic Research institute Wuhan University of Technology Wuhan 430070 China

Single crystal of a new compound Na2.1Ba0.9Cu0.1Nb4.9O14.3 was synthesised for the first time. The crystal structure has been determined by single crystal X-ray diffraction and the final R value is 0. 0559. The compound crystallizes in a tetragonal unit cell [a = 12. 442(3) A and c = 3. 954 A ]with space growp P4/mbm and Z=2. The compound is in tetragonal tungsten-bronze type structure but some oxygen vacancies exist in the structure. The structure of the compound consists of NbO6 octahedra and octahedra (Nb, Cu)O6 to form triangle, quadrilateral and pentagonal tunnels. The quadrilateral tunnels are occupied by Na atoms. More than 1/2 pentagonal tunnels are occupied by Na atoms and less than 1/2 that are occupied by Ba atoms. Cu2+ replaces Nb5+ to form different-valence isomorpism.

关键词： tungsten bronze niobate sythesis crystal

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