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Robust interface and excellent as-built mechanical properties of Ti–6Al–4V fabricated through laser-aided additive manufacturing with powder and wire

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 154-168页

作者： Fei Weng Guijun Bi Youxiang chew Shang Sui chaolin Tan Zhenglin Du Jinlong Su Fern lan ng Key laboratory for liquid-Solid Structural Evolution and Processing of Materials Ministry of EducationShandong Engineering&Technology Research Center for Superhard MaterialSchool of Materials Science and EngineeringShandong UniversityJinan 250061China Institute of Intelligent Manufacturing Guangdong Academy of SciencesGuangzhou 510095China Singapore Institute of Manufacturing Technology 5 Cleantech Loop636732Singapore

The feasibility of manufacturing Ti-6Al-4V samples through a combination of laser-aided additive manufacturing with powder(lAAM_(p))and wire(lAAM_(w))was explored.A process study was first conducted to successfully circumvent defects in Ti-6Al-4V deposits for lAAM_(p) and lAAM_(w),*** the optimized process parameters,robust interfaces were achieved between powder/wire deposits and the forged substrate,as well as between powder and wire *** characterization results revealed the epitaxial prior β grains in the deposited Ti-6Al-4V,wherein the powder deposit was dominated by a finerα′microstructure and the wire deposit was characterized by lamellar α *** mechanisms of microstructure formation and correlation with mechanical behavior were analyzed and *** mechanical properties of the interfacial samples can meet the requirements of the relevant Aerospace Material Specifications(AMS 6932)even without post heat *** fracture occurred within the interfacial area,further suggesting the robust *** findings of this study highlighted the feasibility of combining lAAM_(p) and lAAM_(w) in the direct manufacturing of Ti-6Al-4V parts in accordance with the required dimensional resolution and deposition rate,together with sound strength and ductility balance in the as-built condition.

关键词： laser-aided additive manufacturing powder deposition wire deposition interfacial characteristic mechanical behavior

Calibration of the Solar x-ray Detector on-board the Macao Science Satellite-1B for Soft x-ray Detection

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Science china Earth Sciences 2025年第1期68卷 11-26页

作者： Man-Hei ng xiaoping ZHAng Jianwu chEN Yongqiang SHI Fuchang ZuO Wenxi PEng Weichun Fu liansheng lI Pengwei luO chi-long TAng Guozheng ZHAng Zhiwu MEI li WAng Cunhui lI Jiaming Ou Yanyan xu State Key laboratory of lunar and Planetary Sciences Macau University of Science and Technology china National Space Administration (CNSA) Macau Center for Space Exploration and Science Space Optoelectronic Measurement and Perception laboratory Beijing Institute of Control Engineering Institute of High Energy Physics Chinese Academy of Sciences Science and Technology on Vacuum Technology and Physics laboratory Lanzhou Institute of Physics

The Solar x-ray Detector(SxD) on-board the Macao Science Satellite-1B(MSS-1B) was successfully launched via the chinese long March-2C rocket on 21 May 2023, and commenced operations in early June of the same year. The MSS-1B/Soft x-ray Detection units(SxDus) employ two silicon drift detectors(SDDs), providing a wide range of energy spectra spanning from 0.7 to 24 keV. Notably, the SxDus deliver a high-resolution capability of 0.14 keV@5.9 keV and operate with a time cadence of 1 second. Here, we perform thorough calibrations of the MSS-1B/SxDus, employing a combination of ground experiments and simulations. In addition, quantitative analysis comparing the flux measurements obtained by the MSS-1B/SxDus to the data collected by the Geostationary Operational Environmental Satellite(GOES), provides compelling evidence of their consistency. Furthermore, the preliminary spectral analysis results showcase the robustness and expected performance of the MSS-1B/SxDus, unlocking their potential for facilitating the study of dynamic evolution of solar flares. Moreover, the innovative MSS-1B/Solar x-ray Detector facilitates concurrent observations of solar soft and hard x-rays, thereby making valuable contributions to the advancements in solar research.

关键词： Macao Science Satellite-1B (MSS-1B) Calibration Solar x-Ray Detector Spectrometer Soft x-rays Solar flares Solar abundances

Force and impulse multi-sensor based on flexible gate dielectric field effect transistor

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 214-220页

作者： chao Tan Junling lü chunchi Zhang Dong liang lei Yang Zegao Wang College of Materials Science and Engineering Sichuan UniversityChengdu 610065China The 54th Research Institute of china Electronics Technology Group Corporation Shijiazhuang 050081China

Nowadays,force sensors play an important role in industrial production,electronic information,medical health,and many other ***-dimensional material-based filed effect transistor(2D-FET)sensors are competitive with nano-level size,lower power consumption,and accurate ***,few of them has the capability of impulse detection which is a path function,expressing the cumulative effect of the force on the particle over a period of *** we fabricated the flexible polymethyl methacrylate(PMMA)gate dielectric MoS_(2)-FET for force and impulse sensor *** systematically investigated the responses of the sensor to constant force and varying forces,and achieved the conversion factors of the drain current signals(I_(ds))to the detected impulse(I).The applied force was detected and recorded by I_(ds)with a low power consumption of~30 *** sensitivity of the device can reach~8000%and the 4×1 sensor array is able to detect and locate the normal force applied on ***,there was almost no performance loss for the device as left in the air for two months.

关键词： flexible gate dielectric transistor force sensor impulse sensor force sensor array

Viscosity and structure relationship with equimolar substitution of CaO with MgO in the CaO–MgO–Al_(2)O_(3)–SiO_(2)slag melts

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 70-79页

作者： Yong Hou Shuo Zhang Jie Dang Jia Guo Hanghang Zhou xuewei lü College of Materials Science and Engineering Chongqing UniversityChongqing 400044China chongqing Key laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

Currently,the Al_(2)O_(3)content in the high-alumina slag systems within blast furnaces is generally limited to 16wt%–18.5wt%,making it challenging to overcome this *** most studies that concentrated on managing the MgO/Al_(2)O_(3)ratio or basicity,this paper explored the effect of equimolar substitution of MgO for CaO on the viscosity and structure of a high-alumina CaO-MgO-Al_(2)O_(3)-SiO_(2)slag system,providing theoretical guidance and data to facilitate the application of high-alumina *** results revealed that the viscosity first decreased and then increased with higher MgO substitution,reaching a minimum at 15mol%MgO *** transform infrared spectroscopy(FTIR)results found that the depths of the troughs representing[SiO_(4)]tetrahedra,[AlO_(4)]tetrahedra,and Si-O-Al bending became progressively deeper with increased MgO *** of the Raman spectra showed that the average number of bridging oxygens per Si atom and the x_(Q^(3))/x_(Q^(2))(x_(Q^(i))is the molar fraction of Q^(i) unit,and i is the number of bridging oxygens in a[SiO_(4)]tetrahedral unit)ratio increased from 2.30 and 1.02 to 2.52 and 2.14,respectively,indicating a progressive polymerization of the silicate structure.x-ray photoelectron spectroscopy(xPS)results highlighted that non-bridging oxygen content decreased from 77.97mol% to 63.41mol% with increasing MgO concentration,whereas bridging oxygen and free oxygen contents *** analysis demonstrated a gradual increase in the polymerization degree of the tetrahedral structure with the increase in MgO ***,bond strength is another important factor affecting the slag *** occurrence of a viscosity minimum can be attributed to the complex evolution of bond strengths of non-bridging oxygens generated during depolymerization of the[SiO_(4)]and[AlO_(4)]tetrahedral structures by CaO and MgO.

关键词： aluminosilicate viscosity structure spectroscopy

STRAIN RATE SENSITIVITY OF ulTRAFINE-GRAINED Cu WITH NANOSIZED TWINS

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Acta Metallurgica Sinica(English letters) 2006年第5期19卷 313-318页

作者： l.x. liu x.H. chen l. lu Shenyang National laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

An ultrafine-grained Cu sample with a high density of growth twins was synthesized by means of pulsed electrodeposition technique. The strain rate sensitivity of the Cu sample was measured by strain rate cycling tests under tension. The effects of grain size as well as twin density on the strength and strain rate sensitivity were discussed.

关键词： copper nanosized twin strain rate sensitivity deformation mechanism

Fluid-structure interaction in Z-shaped pipe with different supports

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Acta Mechanica Sinica 2020年第2期36卷 513-523页

作者： Q.Guo J.x.Zhou x.l.Guan College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China Highway Science and Technology Research Institute Xinjiang Production and Construction Corpsürümqi 830002China

Fluid-structure interaction(FSI)has a strong relation with layout of fluid delivery *** is liable to cause local ***,FSI analysis is necessary in many cases,especially for flexible pipe *** modeling consists of eight governing equations and then completely solved via the finite volume method(FVM).Friction,Poisson and joint couplings were discussed in detail to reveal the influence of a Z-shaped pipe with different supports and elbows on *** the feasibility of solving FSI by FVM was verified,the different effects of free,fixed and elastic supports on FSI in the commonly used and simplified Z-shaped pipe were further *** indicated that different support stiffness lead to various FSI *** coupling occurs at the elbow and less support is considered,then the pipe has a relatively large amplitude and complex pressure fluctuation.

关键词： Fluid-structure interaction Finite volume method Z-shaped pipe Support stiffness

FINITE ElEMENT ANAlYSIS OF VISCOuS FlOW PAST A ROTATIng SPHERE

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Journal of Hydrodynamics 2001年第2期13卷 80-85页

作者： Wang, Y.x. lu, x.Y. Zhuang, l.x. Dept. of Modern Mech. Univ. of Sci. and Technol. of China Hefei 230026 China

Viscous flow past a rotating sphere with a constant rotating speed about an axis aligned with the free stream was investigated numerically by solving the three-dimensional Navier-Stokes equations using the finite element method. To elucidate the character of this flow in the near wake, the flow structures at different Reynolds numbers and rotating speeds are examined. The axisymmetric and non-axisymmetric flow structures were observed at Re=200 and 250, respectively, which rotate as a whole around the rotating axis steadily. At Re=300, the vortex shedding appears and the wake becomes more complicated. At low rotating speeds, the flow is dominated by the vortex shedding at higher Reynolds numbers. As the rotating speed increases, the rotating effect gets stronger and the interaction between the rotating action and the vortex shedding results a swirling vortex pattern in the near wake of the sphere.

关键词： Finite element method Navier Stokes equations Numerical methods Three dimensional

Approximate Augmented lagrangian Functions and Nonlinear Semidefinite Programs

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Acta Mathematica Sinica,English Series 2006年第5期22卷 1283-1296页

作者： x.x.HuAng K.l.TEO x.Q.YAng School of Management Fudan University Shanghai 200433 P. R. China and Department of Mathematics and Computer Science Chongqing Normal UniversityChongqing 400047 P. R. China Department of Mathematics and Statistics Curtin University of Technology Perth Australia Department of Applied Mathematics The Hong Kong Polytechnic UniversityKowloon Hong Kong P. R. China

In this paper, an approximate augmented lagrangian function for nonlinear semidefinite programs is introduced. Some basic properties of the approximate augmented lagrange function such as monotonicity and convexity are discussed. Necessary and sufficient conditions for approximate strong duality results are derived. Conditions for an approximate exact penalty representation in the framework of augmented lagrangian are given. under certain conditions, it is shown that any limit point of a sequence of stationary points of approximate augmented lagrangian problems is a KKT point of the original semidefinite program and that a sequence of optimal solutions to augmented lagrangian problems converges to a solution of the original semidefinite program.

关键词： semidefinite programming augmented lagrangian duality exact penalty convergence,stationary point

Elastic-plastic behavior of a semicircular frame being pressed against a rigid plane

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Acta Mechanica Sinica 2008年第4期24卷 419-432页

作者： x.W.Zhang J.l.Yang T.x.Yu Institute of Solid Mechanics Beihang University Beijing 100083 China Department of Mechanical Engineering Hong Kong University of Science and Technology Kowloon Hong Kong China

As a simplified structural model, a semicircular frame is used to study the crashworthiness behavior of an aircraft fuselage. The quasi-static large elastic-plastic deformation of a semicircular frame in the process of its being pressed against a rigid ground is analyzed. First, based on the linear elastic assumption, the quasi-static large deformation contact process of the frame can be divided into three phases, i.e., point contact, line contact and post-buckling. By means of a shooting method, the relations between the displacement and contact force as well as the distribution of bending moment in the three phases are obtained. Then, by assuming an elastic, perfectly-plastic moment-curvature relationship for the semi-circular frame, the contact process is analyzed in detail to reveal the plastic collapse mechanism, the traveling of plastic hinge and the force-displacement relationship. In order to verify the analysis, a preliminary experiment was conducted, in which two types of half rings with clamped ends were pressed by a rigid plate. In addition, a numerical simulation is also conducted by employing ABAQuS to analyze both rectangular cross-sectional beam and I-beam. Finally, the theoretical predictions are compared with the experimental results and numerical solutions, showing that the elastic-plastic analysis can predict the contact process very well.

关键词： Elastic-plastic·large deformation ·Semicircular frame Contact ·Traveling hinge