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11th International Conference on Applied sciences, ICAS 2023

作者： Kostal, P. Telek, P. Matusova, M. Slovak University of Technology Faculty of Material Science and Technology Institute of Production Technologies J. Bottu 25 Trnava91724 Slovakia University of Miskolc Faculty of Mechanical Engineering and Informatics Institute of Logistics Egyetemváros Miskolc Hungary

Current engineering production is characterised by rapid changes. These changes arise due to the shortening of product life cycles. Manufacturers are forced to introduce upgraded products at shorter intervals based on customer requirements. In this paper, we focus on the possibilities of production upgrading by using a group technology in the flexible manufacturing system. The production capabilities of one of the production machines in the manufacturing system will be analysed. This production machine is a lathe that produces one of the essential parts of a finished product. Determine what variations of this part can be produced without changing the physical configuration of the machine. © 2024 Institute of Physics Publishing. All rights reserved.

关键词： Flexible manufacturing systems

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Effect of infill pattern on fatigue characteristics of 3D printed polymers

Effect of infill pattern on fatigue characteristics of 3D pr...

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作者： Dudescu, Mircea Cristian Racz, Laszlo Popa, Florin Department of Mechanical Engineering Technical University of Cluj-Napoca 103-105 Muncii Boulevard Cluj-Napoca400641 Romania Department of Material Science and Engineering Technical University of Cluj-Napoca 103-105 Muncii Boulevard Cluj-Napoca400641 Romania

The effect of the structure that is printed inside an object, known as infill pattern, on fatigue life of 3D printed specimens made of ABS was investigated in this paper. There are several infill pattern geometries, each with benefits and compromises between material usage, printing time or mechanical strength of the obtained part. Standard specimens with 100 % infill rate and rectilinear 0° and 90°, grid 0°–90° and ± 45°, triangular 60°, fast honeycomb, full honeycomb and wiggle infill patterns were tested. Following the completion of tensile tests to determine the ultimate tensile strength (UTS) of specimens, axial fatigue tests for each combination of infill pattern were conducted to measure the fatigue life for 90 %, 75 %, 60 %, 45 % and 40 % UTS. Comparative evaluation of the measured values revealed the strong influence of the printing patterns upon fatigue life. A simple mathematical model of the fatigue proprieties has been proposed for each infill patterns, statistical data shows that the proposed model ensures reasonably accurate prediction of fatigue life. The examination of fracture areas using electronic microscopy indicated the microstructural interaction between filaments underlying the main failure mechanisms, crazing, delamination and disbonding of the filaments and layers and their fracture. The results indicate that pattern with inclined filaments about tensile axis (grid±45°, rectilinear 0° and triangular 60°) have the maximum fatigue life compared with those with most of the filaments perpendicular to tensile direction (fast honeycomb, full honeycomb and rectilinear 90°). The pattern like grid 0°–90° and wiggle are very close to the first group, having filaments inclined (wiggle) or along and perpendicular to the tensile direction (grid 0°–90°). © 2022

关键词： Tensile strength

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UV-ASSISTED 3D FORMATION OF CONTINUOUS FIBER/THERMOSET EPOXY COMPOSITES

UV-ASSISTED 3D FORMATION OF CONTINUOUS FIBER/THERMOSET EPOXY...

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SAMPE 2023 Conference and Exhibition

作者： Deng, Kaiyue Zhang, Chunyan Fu, Kun K. Department of Mechanical Engineering University of Delaware NewarkDE19716 United States Department of Material Science and Engineering University of Delaware NewarkDE19716 United States Center for Composite Materials University of Delaware NewarkDE19716 United States

ISBN: (纸本)9781934551431

Fiber-reinforced polymer composites (FRPCs) using continuous fibers and thermosetting polymers are widely used because of the excellent specific mechanical properties, thermal stability, and chemical resistance. The development of cost-effective and mold-free manufacturing processes for FRPCs with manufacturing flexibility and 3D structure has received extensive research attention. Here, we report a UV-assisted 3D formation approach to coat thin UV resin layers on both sides of the raw material (Fiber tow, prepreg) to enable a fast curing on the interface to achieve good interfacial bonding to form a solid three-dimensional (3D) object. The continuous fiber/thermoset epoxy composites made with prepreg (unidirectional carbon fabric) and UV resin serving as the layer binder by this route were investigated to demonstrate the feasibility and generality of the proposed technique. The mechanical testing results showed the manufactured composite exhibited a tensile strength of 1075.27 MPa and modulus of 45.24 MPa;a flexural strength of 1209.50 MPa and modulus of 68.01 GPa;and interlaminar strength of 37.17 MPa. © 2023 Soc. for the Advancement of material and Process engineering. All rights reserved.

关键词： Epoxy composites

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Parametric Control via the Algebraic Expression of Lotus-Type Pore Shapes in Metals

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materials 2024年第12期17卷 3013页

作者： Wang, Liwei Lee, Bo-Yue Wei, Peng-Sheng Quan, Mingming School of Material Science and Engineering Hebei University of Science and Technology Shijiazhuang050018 China Department of Mechanical and Electro-Mechanical Engineering National Sun Yat-sen University Kaohsiung80424 Taiwan

Lotus-type porous metals, characterized by low densities, large surface areas, and directional properties, are contemporarily utilized as lightweight, catalytic, and energy-damping materials;heat sinks;etc. In this study, the effects of dimensionless working parameters on the morphology of lotus-type pores in metals during unidirectional solidification were extensively investigated via general algebraic expressions. The independent dimensionless parameters include metallurgical, transport, and geometrical parameters such as Sieverts’ law constant, a partition coefficient, the solidification rate, a mass transfer coefficient, the imposed mole fraction of a solute gas, the total pressure at the top free surface, hydrostatic pressure, a solute transport parameter, inter-pore spacing, and initial contact angle. This model accounts for transient gas pressure in the pore, affected by the solute transfer, gas, capillary, and hydrostatic pressures, and Sieverts’ laws at the bubble cap and top free surface. Solute transport across the cap accounts for solute convection at the cap and the amount of solute rejected by the solidification front into the pore. The shape of lotus-type pores can be described using a proposed fifth-degree polynomial approximation, which captures the major portions between the initial contact angle and the maximum radius at a contact angle of 90 degrees, obtained by conserving the total solute content in the system. The proposed polynomial approximation, along with its working parameters, offers profound insights into the formation and shape of lotus-type pores in metals. It systematically provides deep insights into mechanisms that may not be easily revealed with experimental studies. The prediction of a lotus-type pore shape is thus algebraically achieved in good agreement with the available experimental data and previous analytical results. © 2024 by the authors.

关键词： Solidification

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A Hybrid Rolling and Flying Robot for Pipeline Fault Detection Using Deep Learning

A Hybrid Rolling and Flying Robot for Pipeline Fault Detecti...

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2023 Advances in science and engineering Technology International Conferences, ASET 2023

作者： Ghaly, Megan Mitra, Rohan Rayess, Abdullah Al Ahmed, Assem Varam, Dara Jaradat, Mohammad A. Pasquier, Michel Khalil, Ahmed American University of Sharjah Department of Mechanical Engineering Sharjah United Arab Emirates American University of Sharjah Department of Computer Science and Engineering Sharjah United Arab Emirates American University of Sharjah Mechatronics Engineering Gradute Program Sharjah United Arab Emirates

ISBN: (纸本)9781665454742

The Middle Eastern and North African region is highly reliant on the oil and gas industry. Subsequently, the need for pipeline inspection and fault diagnosis has become paramount. Current inspection methods rely on manual procedures that introduce sources of error into the results. In this paper, the design for a hybrid rolling and flying unmanned aerial vehicle (UAV) for pipeline inspection is proposed. The UAV was developed with a rolling frame capable of landing on pipelines to externally inspect them for cracks, leaks, or faults by traversing along the pipeline's surface while maintaining its stability. The hybrid UAV uses a camera to classify cracks along the surface of the pipeline using deep learning models. The paper then tests several models and deploys the best model found during testing -MobileNet100 along with the proposed design for the UAV. Finally, the prototype that was presented in this paper has been tested within a controlled environment to verify the compliance of the flying, rolling and fault detection subsystems. © 2023 IEEE.

关键词： Fault detection

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Optothermal multimodal manipulation of micro/nanoparticles

Optothermal multimodal manipulation of micro/nanoparticles

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2023 Conference on Lasers and Electro-Optics, CLEO 2023

作者： Ding, Hongru Kollipara, Pavana Siddhartha Yao, Kan Zheng, Yuebing Walker Department of Mechanical Engineering The University of Texas at Austin AustinTX78712 United States Materials Science & Engineering Program Texas Materials Institute The University of Texas at Austin AustinTX78712 United States

ISBN: (纸本)9781957171258

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Thermal energy dependent transient permittivity of epsilon-near-zero material

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science China(Physics,Mechanics & Astronomy) 2022年第8期65卷 96-101页

作者： Heng Wang Lixun Sun Kang Du Wending Zhang SooJin Chua Guixin Li Ting Mei MOE Key Laboratory of Material Physics and Chemistry under Extraordinary Conditions and Shaanxi Key Laboratory of Optical Information TechnologySchool of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi’an710129China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen518055China Shenzhen Institute for Quantum Science and Engineering Southern University of Science and TechnologyShenzhen518055China Department of Electrical and Computer Engineering National University of SingaporeSingapore117583Singapore LEES Program Singapore-MIT Alliance for Research&Technology(SMART)Singapore138602Singapore

Transparent conductive oxides exhibit attractive optical nonlinearity with ultrafast response and giant refractive index change near the epsilon-near-zero(ENZ) wavelength, originating from the intraband dynamics of conduction electrons. The optical nonlinearity of ENZ materials has been explained by using the overall-effective-mass and the overall-scattering-time of electrons in the extended Drude model. However, their response to optical excitation is yet the last building block to complete the theory. In this paper, the concept of thermal energy is theoretically proposed to account for the total energy of conduction electrons exceeding their thermal equilibrium value. The time-varying thermal energy is adopted to describe the transient optical response of indium-tin-oxide(ITO), a typical ENZ material. A spectrally-resolved femtosecond pump-probe experiment was conducted to verify our theory. By correlating the thermal energy with the pumping density, both the giant change and the transient response of the permittivity of ITO can be predicted. The results in this work provide a new methodology to describe the transient permittivities of ENZ materials, which will benefit the design of ENZ-based nonlinear photonic devices.

关键词： epsilon-near-zero optical nonlinearity transient response thermal energy hot electron indium tin oxide

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Manufacturable Novel Nanogrease with Superb Physical Properties

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Nanomanufacturing and Metrology 2021年第4期4卷 289-297页

作者： Hammad Younes Ding Lou Haiping Hong Huahui Chen Hongtao Liu Yinhuai Qiang Department of Electrical Engineering South Dakota School of Mines and TechnologyRapid CitySD 57701USA Department of Material Science and Engineering School of Mechanical and Electrical EngineeringChina University of Mining and TechnologyBeijing 100083China School of Material Science and Engineering China University of Mining and TechnologyXuzhou 221166China

High-performance nanogrease manufactured from carbon nanomaterials is observed to be stable and homogeneous and have superb physical properties,such as thermal and electrical conductivities,compared with current commercial greases made of lithium,calcium,and *** the first time,carbon nanomaterials have been observed to disperse well as the sole thickeners in oil systems,e.g.,polyalphaolefin and polyester(ROYCO),without the aid of any chemical ***-dimensional percolation network structures that exist among carbon nanomaterials are easily scalable,which can be attributed to the intermolecular van der Waals ***,the introduction of hydrogen bonding in any form to grease significantly increases its thermal and electrical conductivities and substantially reduces the weight percentage of carbon nanomaterials needed to fabricate stable *** example,loading of only 1.4 wt%hydroxyl-functionalized multiwalled carbon nanotube(MWNT-OH)with Krytox XHT750 oil leads to a 37.8%increase in thermal ***,75%glycerol,25% water,and 4.5 wt% MWNT-OH yielded the lowest electrical resistivity of 10.0 Ω *** finding can be extended to hydrogen bonding materials with functional groups,such as OH,COOH,F,and *** nanogrease reported in this study has been manufactured using the three-roll mill method,which is an easy and cost-effective method,as the loading weight percentage of carbon nanomaterials to fabricate stable grease decreases from 12 wt% to 3-4 wt%.Furthermore,the process is easily scalable,reproduced,and *** novel high-performance nanogrease has a high commercial value and numerous applications and could replace current commercial greases.

关键词： Nanogrease Three-dimensional network percolation structure Carbon nanomaterial Van der Waals forces Hydrogen bonding Thermal conductivity Electrical conductivity

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Effect of Heat Treatments on Microstructure and mechanical Properties of Fe-Mn-Ni-Al-Gd Shape Memory Alloy

Effect of Heat Treatments on Microstructure and Mechanical P...

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2023 Sharjah International Conference on Physics of Advanced materials, SICPAM 2023

作者： Mustafa, Faisal Egilmez, Mehmet Abuzaid, Wael El-Khatib, Sami Department of Physics American University of Sharjah Sharjah26666 United Arab Emirates Materials Science and Engineering Program American University of Sharjah Sharjah26666 United Arab Emirates Department of Mechanical Engineering American University of Sharjah Sharjah26666 United Arab Emirates

There are significant scientific and industrial efforts to develop and optimize Iron-based shape memory alloys (SMA) such as FeMnNiAl for cost-sensitive applications. This alloy system shows shape memory and superelastic properties across a large temperature range. However, many studies have pointed out the need for rather complex thermo-mechanical treatments for the optimization of the SMA properties. In addition, works considering the effects of alloying on the development of microstructures that are more conducive to pseudo-elasticity in this system remain limited. Hence, systematic studies aiming at the investigation of the microstructural evolution of the FeMnNiAl(Gd) system are of great interest. In this study, solution heat treatment is done to tune the microstructure for optimum mechanical properties. The effect of phase distribution on mechanical properties is investigated at different heat treatments. Whereas cyclic heat treatment induced abnormal grain growth (AGG) in all samples, so large grains were obtained. The phase variation and elemental composition are analyzed by X-ray diffraction and Energy Dispersive Spectroscopy, respectively. The microstructure and phase distribution are observed using Scanning Electron Microscope and then related to the microhardness results. The microstructure has a good correlation with mechanical properties where the fine distribution of phases results in a higher hardness number. © Published under licence by IOP Publishing Ltd.

关键词： Microstructure

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CALPHAD coupled phase-field simulation of microstructural evolution during active metal brazing with Ag-Cu-Sn-Ti alloy 28

CALPHAD coupled phase-field simulation of microstructural ev...

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28th Congress of the International Federation for Heat Treatment and Surface engineering, IFHTSE 2023

作者： Morino, Takumi Hirosawa, Shoichi Ode, Machiko Abe, Taichi Mori, Yoichiro Suenaga, Seiichi Department of Mechanical Engineering and Materials Science Yokohama National University 79-5 Tokiwadai Hodogaya-ku Kanagawa Yokohama240-8501 Japan Computational Material Science Center National Institute of Material Science Ibaraki Tsukuba305-0047 Japan Toshiba Materials Corporation Kanagawa Yokohama235-8522 Japan

ISBN: (纸本)9781713889533

In this study, a new CALPHAD database of Ag-Cu-Sn-Ti system has been proposed, followed by a phase-field simulation to predict the solidification microstructure of the quaternary alloy during active metal brazing that joins copper circuits and Si3N4 substrates. From the CALPHAD coupled phase-field simulation, it was revealed that melting of copper circuit and a reaction of Ti with Si3N4 substrate decreases the amount of primary Sn3Ti5, resulting in an increased Sn concentration within Ag-Cu-Sn-Ti liquid and thus a lowering of the temperature at which solidification of the brazing metal is completed. Therefore, the developed phase-field program of our own coding can successfully clarify the effect of copper circuit melting and Ti depletion during active metal brazing, which cannot be experimentally monitored. © 2023 28th IFHTSE 2023 Congress. All rights reserved.

关键词： Tin alloys

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