Achieving high strength in Mg alloys is usually accompanied by ductility ***,a novel Mg97Y1Zn1Ho1 at.%alloy with a yield strength of 403 MPa and an elongation of 10%is *** strength-ductility synergy is obtained by a c...
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Achieving high strength in Mg alloys is usually accompanied by ductility ***,a novel Mg97Y1Zn1Ho1 at.%alloy with a yield strength of 403 MPa and an elongation of 10%is *** strength-ductility synergy is obtained by a comprehensive strategy,including a lamella bimodal microstructure design and the introduction of nano-spaced solute-segregated 14H long-period stacking-ordered phase(14H LPSO phase)through rare-earth Ho *** lamella bimodal microstructure consists of elongated un-recrystallized(un-DRXed)coarse grains and fine dynamically-recrystallized grains(DRXed regions).The nano-spaced solute-segregated 14H LPSO phase is distributed in DRXed *** outstanding yield strength is mainly contributed by grain-boundary strengthening,18R LPSO strengthening,and fiberlike reinforcement strengthening from the nano-spaced 14H LPSO *** high elongation is due primarily to the combined effects of the bimodal and lamellar microstructures through enhancing the work-hardening capability.
Background: With the rapid development of China's economy and the accelerating process of agricultural mechanization, agricultural machinery has become increasingly popular in agricultural production activities. A...
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Understanding the non-equilibrium phase transition mechanism is critical to controlling the transform-ing microstructures and thus material *** order to improve the problem of low room-temperature ductility of TiAl al...
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Understanding the non-equilibrium phase transition mechanism is critical to controlling the transform-ing microstructures and thus material *** order to improve the problem of low room-temperature ductility of TiAl alloys with traditional microstructures,a two-step forging with an interme-diate heat preservation process is proposed to prepare a hybrid microstructure via non-equilibrium phase transition in this *** hybrid microstructure is composed ofβ_(0)/γlamellar colony,a structure with innerα_(2)/γand outerβ_(0)/γlamellae surrounded byβ_(0)phase,a structure ofγgrains embedded withinα_(2)/γlamellar colony,and some granularβ_(0)withinγ*** hybrid microstructure exhibits excellent room-temperature mechanical properties with a total elongation to failure of 2.15%and tensile strength of 920 ***,the evolution mechanisms of these various structures are analyzed from the perspective of solute element diffusion and distribution in front of the phase transition ***-gation of V element in front of theγgrowth interface induces the elemental reaction deviating from the equilibrium phase transitionα→α_(2)+γ,andα→β(β_(0))+γtransition occurs,resulting in the formation ofβ(β_(0))/γlamellar *** hot forging,α→α_(2)+γtransition occurs to generateα_(2)/γlamellae in the initial transition stage(I)of solute *** the stable stage(II),the content of V element in front of the growth interface ofγlamellae increases to∼18.41%,andα→β(β_(0))+γtransition occurs,soβ(β_(0))/γlamellae are formed outside theα_(2)/γlamellar *** the final stage(III),the remainingαphase is less,and the diffusion of the V element is hindered,causing a sudden increase of the V element inαphase,resulting in the remainingαphase transformed into irregularβ(β_(0))***,the structure with innerα_(2)/γand outerβ_(0)/γlamellae surrounded byβ_(0)phase is ***,adjusting the cooling rate realizes the precise controlling of theα_(2)/γ,β_(0)
Background: With the increase in the motorized spindle speed, the heating problem of the spindle has become a key factor affecting machining accuracy and efficiency. Because of this, the patent technology related to c...
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Background: With the increase in the motorized spindle speed, the heating problem of the spindle has become a key factor affecting machining accuracy and efficiency. Because of this, the patent technology related to cooling the main shaft is being analyzed. Aiming at technical problems, such as temperature rise control due to the high speed of motorized spindle and its structural integration, this paper systematically analyzes and deeply summarizes the existing cooling technology achievements for high-speed motorized spindles, expounds the cooling technology for key components of these high-speed motorized spindle, and discusses the application of a more economical and effective cooling technology for engineering in junior high school to overcome future challenges. The paper also forecasts future development trends. The heating caused by the highspeed rotation of the motorized spindle motor and the friction-induced heating of the bearings are inevitable. After the temperature rise, the relative position and size of the spindle and other parts or components of the machine tool will differ from that before the temperature rose, forming different temperature fields and then producing different degrees of thermal expansion, leading to processing errors. This paper analyzes the characteristics and application scenarios of various cooling mechanisms for motorized spindles. Objective: By analyzing and discussing the patents related to the cooling methods of motorized spindles, this study aims to explore the factors of temperature variation during the working process of the motorized spindle and seeks to predict future research and development in motorized spindle cooling equipment. Methods: The present status of various representative patents related to the cooling device of the motorized spindle was analyzed, and the influence of the cooling device of the motorized spindle on the working effect of the spindle was obtained. According to the classification of the characteri
Plasma,the fourth state of matter,is characterized by the presence of charged particles,including ions and *** has been shown to induce unique physical and chemical ***,there have been increased applications of plasma...
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Plasma,the fourth state of matter,is characterized by the presence of charged particles,including ions and *** has been shown to induce unique physical and chemical ***,there have been increased applications of plasma technology in the field of multiscale functional materials'preparation,with a number of interesting *** review will begin by introducing the basic knowledge of plasma,including the definition,typical parameters,and classification of plasma *** this,we will provide a comprehensive review and summary of the applications(phase conversion,doping,deposition,etching,exfoliation,and surface treatment)of plasma in common energy conversion and storage systems,such as electrocatalytic conversion of small molecules,batteries,fuel cells,and *** article summarizes the structure-performance relationships of electrochemical energy conversion and storage materials(ECSMs)that have been prepared or modified by *** also provides an overview of the challenges and perspectives of plasma technology,which could lead to a new approach for designing and modifying electrode materials in ECSMs.
A smooth bidirectional evolutionary structural optimization(SBESO),as a bidirectional version of SESO is proposed to solve the topological optimization of vibrating continuum structures for natural frequencies and dyn...
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A smooth bidirectional evolutionary structural optimization(SBESO),as a bidirectional version of SESO is proposed to solve the topological optimization of vibrating continuum structures for natural frequencies and dynamic compliance under the transient load.A weighted function is introduced to regulate the mass and stiffness matrix of an element,which has the inefficient element gradually removed from the design domain as if it were undergoing *** at maximizing the natural frequency of a structure,the frequency optimization formulation is proposed using the SBESO *** effects of various weight functions including constant,linear and sine functions on structural optimization are *** the equivalent static load(ESL)method,the dynamic stiffness optimization of a structure is formulated by the SBESO *** examples show that compared with the classic BESO method,the SBESO method can efficiently suppress the excessive element deletion by adjusting the element deletion rate and weight *** is also found that the proposed SBESO technique can obtain an efficient configuration and smooth boundary and demonstrate the advantages over the classic BESO technique.
With the rapid development of medical imaging technology, Computed Tomography (CT) has become an indispensable tool in medical diagnosis. However, in the application of medical image segmentation, there are still some...
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The application of aramid fiber(AF)/polyetheretherketone(PEEK)composites is currently hindered by the inert surface and poor wettability of AF,resulting in weak interfacial adhesion and poor mechani-cal *** coating an...
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The application of aramid fiber(AF)/polyetheretherketone(PEEK)composites is currently hindered by the inert surface and poor wettability of AF,resulting in weak interfacial adhesion and poor mechani-cal *** coating and the introduction of nanostructures have been proven to be effective approaches to address this ***,a simple hybrid sizing agent has been developed to modify the AF surface,consisting of soluble polyimide(PI)as a compatibilizer,carboxyl-functionalized carbon nanotubes(CNT-COOH)as a rigid unit,and aramid nanofibers(ANF)as a flexible *** syner-getic effects of PI and the multiscale flexible-rigid structure(CNT-COOH/ANF)contribute to the formation of chemical and physical bonds between AF and PEEK matrix,further improving the interfacial adhesion and stress transfer *** to the enhanced wettability and roughness of AF,compared with unsized AF,the flexural strength(220.97 MPa),modulus(13.26 GPa),ILSS(13.36 MPa),and storage modu-lus(12.93 GPa)of the AF/PEEK composite increase by 132.60%,99.00%,18.97%,and 82.70%***,the flexible-rigid nanonetwork facilitates the penetration of the PEEK resin into pore *** simple and effective approach exhibits promising potential in enhancing the interfacial bonding of AF/PEEK composites.
This paper introduces a novel approach to reduce computational latencies in cloud platforms by integrating data compression with Non-Orthogonal Multiple Access (NOMA) technologies. We propose a computational task offl...
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Broadband photodetectors with self-driven functions have attracted intensive scientific interest due to their low energy consumption and high optical ***,high-performance broadband self-driven photodetectors are still...
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Broadband photodetectors with self-driven functions have attracted intensive scientific interest due to their low energy consumption and high optical ***,high-performance broadband self-driven photodetectors are still a significant challenge due to the complex fabrication processes,environmental toxicity,high production costs of traditional 3D semiconductor materials and sharply raised contact resistance,severe interfacial recombination of 2D materials and 2D/3D mixed dimension ***,1D p-Te/2D n-Bi_(2)Te_(3) heterojunctions are constructed by the simple and low-cost hydrothermal method.1D p-Te/2D n-Bi_(2)Te_(3) devices are applied in photoelectrochemical(PEC)photodetectors,with their high performance attributed to the good interfacial contacts reducing interface *** device demonstrated a broad wavelength range(365–850 nm)with an Iph/Idark as high as *** R_(i),D^(*),and external quantum efficiency(EQE)values of the device were as high as 12.07 mA/W,5.87×10^(10) Jones,and 41.05%,respectively,which were significantly better than the performance of the prepared Bi_(2)Te_(3) and Te devices.A comparison of the freshly fabricated device and the device after 30 days showed that 1D p-Te/2D n-Bi_(2)Te_(3) had excellent stability with only 18.08%decay of *** is anticipated that this work will provide new emerging material for future design and preparation of a high-performance self-driven broadband photodetector.
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