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A CO-SIMULATION APPROACH BASED ON CLOSE-LOOP FEEDBACK CONTROL FOR ALUMINUM ALLOYS PROFILE EXTRUSION

UPB Scientific Bulletin, Series B: Chemistry and materials science 2023年第2期85卷 243-256页

作者： Zhou, Li Liu, Yan Zhang, Yong Yin, Xuni School of Mechanical and Electrical Engineering Hunan City University China School of Information and Electronic Engineering Hunan City University China School of Material Science and Engineering Central South University China

The conventional simulation for aluminum alloys profile extrusion (AAPE) is an open-loop control system in which the control parameters cannot be adjusted during the simulation process. To address this issue, we use the novel co-simulation method by coupling two kinds of code: using Abaqus code to model the extrusion process and a Python code to model the control unit. Then, a fully coupled feedback closed-loop co-simulation of AAPE is presented in this work. By using the numerical model of the closed-loop control system, the profile outlet temperature is controlled to be balanced and uniform. Moreover, a gradient-heated aluminum billet is simulated in this paper. For this special scenario, it is important to model the AAPE control system by considering the interaction of the die with the aluminum alloys components, resulting in a more accurate representation. © 2023, Politechnica University of Bucharest. All rights reserved.

关键词： Finite element method

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Revealing Hetero-Deformation Induced(HDI)Hardening and Dislocation Activity in a Dual-Heterostructure Magnesium Matrix Composite

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Journal of Magnesium and Alloys 2025年第2期13卷 902-921页

作者： Lingling Fan Ran Ni Lingbao Ren Peng Xiao Ying Zeng Dongdi Yin Hajo Dieringa Yuanding Huang Gaofeng Quan Wei Feng School of Mechanical Engineering Chengdu UniversitySichuanChengdu 610106PR China School of Materials Science and Engineering Southwest Jiaotong UniversitySichuanChengdu 610031PR China State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi'an Jiaotong UniversityShanxiXi'an 710049PR China Institute of Material and Process Design Helmholtz-Zentrum HereonGeesthacht 21502Germany Institute of Metallic Biomaterials Helmholtz-Zentrum HereonGeesthacht 21502Germany

Integrating a heterogeneous structure can significantly enhance the strength-ductility synergy of ***,the relationship between hetero-deformation induced(HDI)strain hardening and dislocation activity caused by heterogeneous structures in the magnesium matrix composite remains *** this study,a dual-heterogeneous TiC/AZ61 composite exhibits significantly improved plastic elongation(PEL)by nearly one time compared to uniform FG composite,meanwhile maintaining a high strength(UTS:417 MPa).This is because more severe deformation inhomogeneity in heterogeneous structure leads to more geometrically necessary dislocations(GNDs)accumulation and stronger HDI stress,resulting in higher HDI hardening compared to FG and CG *** the early stage of plastic deformation,the pile-up types of GND in the FG zone and CG zone are significantly *** tend to form substructures in the FG zone instead of the CG *** only accumulate at grain boundaries of the CG region,thereby leading to obviously increased back stress in the CG *** the late deformation stage,the elevated HDI stress activates the new〈c+a〉dislocations in the CG region,resulting in dislocation entanglements and even the formation of substructures,further driving the high hardening in the heterogeneous ***,For CG composite,〈c+a〉dislocations are not activated even under large plastic strains,and only〈a〉dislocations pile up at grain boundaries and twin *** work provides an in-depth understanding of dislocation variation and HDI hardening in heterogeneous magnesium-based composites.

关键词： Mg-matrix composite Heterogeneous structure HDI hardening GND density Dislocation

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Thermal and Hydraulic Study of Mini-Channel with Irregular Surface Topology 9th

Thermal and Hydraulic Study of Mini-Channel with Irregular S...

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9th International and 49th National Conference on Fluid Mechanics and Fluid Power, FMFP 2022

作者： Rahevar, Vishwajeetsinh Desai, Prayag Pandya, Sheetal Arora, Amit Shah, Niraj Department of Mechanical Engineering Nirma University Ahmedabad India Department of Material Science and Engineering Indian Institute of Technology Gandhinagar India

ISBN: (纸本)9789819978267

The present study aims at identifying the critical Reynolds number for transition from laminar to turbulent in irregular shaped mini-channels. Numerical study including conjugate heat transfer and axial conduction is carried out using commercially available software ANSYS Fluent®. The channel of length 105 mm, width 4.5 mm, and height 2 mm is fabricated in an aluminium substrate of length 114 mm (L), width 15 mm (W), and height 6.3 mm (H). Water is used as working fluid. Average hydraulic diameter (Dh) of mini-channel is 2.86 mm, and cross-section area varies non-uniformly from 10 mm2 to 18 mm2 along the length. Problem is set up with mass flow rate and outflow boundary condition at inlet and outlet, respectively. Bottom wall is given with uniform heat flux (q) of 200 watts thus incorporating conduction in solid wall of channel. Temperature difference between the inlet and outlet is compared with experimental measurement and found to be in good agreement. It is observed that the heat transfer coefficient as well as pressure drop both increases with increase in mass flow rate;however, increase in pressure drop is found larger compared to increase in heat transfer coefficient. Further, we also found the axial conduction in the solid wall. It is interesting to note that the transition from laminar to turbulent is observed at lower Reynolds number. Present work provides platform to study thermal and fluid flow behaviour of the irregular shaped mini-channels. © 2024, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Heat transfer coefficients

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Unveiling the size effect of nitrogen-doped carbon-supported copper-based catalysts on nitrate-to-ammonia electroreduction

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Nano Research 2024年第4期17卷 2438-2443页

作者： Ran Li Taotao Gao Wenxi Qiu Minghao Xie Zhaoyu Jin Panpan Li College of Materials Science and Engineering Sichuan UniversityChengdu 610065China Institute for Advanced Study Chengdu UniversityChengdu 610106China Materials Science and Engineering Program and Walker Department of Mechanical Engineering The University of Texas at AustinAustinTexas 78712USA Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China

The electrocatalytic nitrate reduction reaction(NitRR)represents a promising approach toward achieving economically and environmentally sustainable ***,it remains a challenge to regulate the size effect of electrocatalysts to optimize the catalytic activity and ammonia ***,the Cu-based catalysts were tailored at the atomic level to exhibit a size gradient ranging from single-atom catalysts(SACs,0.15–0.35 nm)to single-cluster catalysts(SCCs,1.0–2.8 nm)and nanoparticles(NPs,20–30 nm),with the aim of studying the size effect for the NO_(3)^(-)-to-NH_(3) reduction ***,the Cu SCCs exhibit enhanced metal–substrate and metal–metal interactions by taking advantageous features of Cu SACs and Cu ***,Cu SCCs achieve exceptional electrocatalytic performance for the NitRR with a maximum Faradaic efficiency of ca.96%NH_(3)and the largest yield rate of ca.1.99 mg·h^(-1)·cm^(-2) at-0.5 V *** hydrogen electrode(RHE).The theoretical calculation further reveals the size effect and coordination environment on the high catalytic activity and selectivity for the *** work provides a promising various size-controlled design strategy for aerogel-based catalysts effectively applied in various electrocatalytic reactions.

关键词： nitrate electroreduction ammonia electrosynthesis size effect single-cluster catalyst

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The strength-ductility synergy of magnesium matrix nanocomposite achieved by a dual-heterostructure

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材料科学技术（英文版） 2025年第12期215卷 296-314页

作者： Lingling Fan Yukai Xiong Ying Zeng Ran Ni Yuwenxi Zhang Lingbao Ren Hajo Dieringa Yuanding Huang Gaofeng Quan Xu Zhang School of Mechanical Engineering Chengdu UniversityChengdu 610106China Key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Material Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China School of Mechanics and Aerospace Engineering Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Material Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China Center for Advancing Materials Performance from the Nanoscale State Key Laboratory for Mechanical Behavior of MaterialsXi'an Jiaotong UniversityXi'an 710049China Institute of Material and Process Design Helmholtz-Zentrum HereonGeesthacht 21502Germany Institute of Metallic Biomaterials Helmholtz-Zentrum HereonGeesthacht 21502Germany

This study aims to achieve a synergy of strength and ductility in magnesium-based nanocomposite ma-terials through the design of a *** ball milling and hot extrusion,a nano-TiC/AZ61 composite featuring particle-rare coarse grain(CG)and particle-rich fine grain(FG)zones was successfully *** results demonstrated that compared with the homogeneous struc-ture,the dual-heterostructure composite achieved a significant increase in elongation by 116％and a remarkable 165％improvement in the strength-ductility product(SDP),while maintaining a high ulti-mate tensile strength(UTS)of 417±4 *** substantial performance enhancement is primarily at-tributed to the additional strain hardening induced by hetero-deformation-induced(HDI)strain harden-ing and crack-blunting capabilities,as elucidated by microstructural characterization and crystal plasticity finite element modeling(CPFEM).Notably,the strain hardening contribution from the CG zones at the early stage of deformation(≤ 45％of total plastic deformation amount)is minimal but increases sig-nificantly during the subsequent deformation *** dislocation increment rate in CG zones(219％)is observed to be more than double that in FG zones(95％),attributed to the large grain size and low dislocation density in CG zones,which provide more space for dislocation *** addition,the aggravated deformation inhomogeneity as deformation progresses leads to an increase in geometrically necessary dislocations(GNDs)generation near the heterogeneous interface,thereby enhancing HDI *** mechanism analysis indicated that the cracks mainly initiate in the FG region and are effectively blunted upon their propagation to the CG region,necessitating increased energy consumption and indicating higher fracture toughness for the dual-heterostructure *** study validates the effectiveness of the dual-heterostructure design in magnesium-based composites,providing a novel u

关键词： Heterostructure Strengthening mechanism Strength-ductility synergy Fracture mechanism Magnesium

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Mechanism and machinability in novel electroplastic-assisted grinding ductile iron

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Advances in Manufacturing 2025年第1期13卷 245-263页

作者： Jia-Hao Liu Dong-Zhou Jia Chang-He Li Yan-Bin Zhang Ying Fu Zhen-Lin Lv Shuo Feng College of Mechanical Engineering and Automation Liaoning University of TechnologyJinzhou121001LiaoningPeople’s Republic of China School of Mechanical&Automotive Engineering Qingdao University of TechnologyQingdao266520ShandongPeople’s Republic of China Songshan Lake Material Laboratory Dongguan523808GuangdongPeople’s Republic of China School of Materials Science and Engineering Xi’an University of TechnologyXi’an710048People’s Republic of China

Owing to the hard brittle phase organization in their matrixes,brittle materials are prone to the formation of pits and cracks on machined surfaces under extreme grinding conditions,which severely affect the overall performance and service behavior of machined *** on the electroplastic effect of pulsed currents during material deformation,this study investigates electroplastic-assisted grinding with different electrical parameters(current,frequency,and duty cycle).The results demonstrate that compared to conventional grinding,the pulsed current can significantly decrease the surface roughness(S_(a))of the workpiece and reduce surface pits and crack *** higher the pulsed current,the more pronounced the improvement in the surface quality of the *** to traditional grinding,when the pulsed current is 1000 A,S_(a) decreases by 46.4%,and surface pit and crack defects are *** the same pulse-current amplitude and frequency conditions,the surface quality continues to improve as the duty cycle *** the duty cycle is 75%,S_(a) reaches a minimum of 0.749μ***,the surface quality is insensitive to the pulsed-current *** investigating the influence of pulsed electrical parameters on the surface quality of brittle material under grinding conditions,this study provides a theoretical basis and technical support for improving the machining quality of hard,brittle materials.

关键词： Electroplasticity Grinding machining Brittle material Pulse parameters Surface quality

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Influences of Milling Time and NbC on Microstructure of AlCoCrFeNi_(2.1)High Entropy Alloy by mechanical Alloying

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Journal of Wuhan University of Technology(materials science) 2023年第2期38卷 423-429页

作者： LI Li JIANG Hui NI Zhiliang HAN Kaiming WANG Rui WANG Haixia College of Mechanical and Electronic Engineering Shandong University of Science and TechnologyQingdao266590China Yangzhou Fengming Photoelectric New Material Co.Ltd Yangzhou225200China

AlCoCrFeNi_(2.1)eutectic high entropy alloy(EHEA)and AlCoCrFeNi_(2.1)-x NbC(x=2.5wt%,5.0wt%,7.5wt%,and 10wt%)high entropy alloy(HEAs)were prepared by mechanical alloying(MA).The effects of milling time and NbC content on the alloying behavior and grain size of the AlCoCrFeNi_(2.1)EHEA were *** experimental results show that the AlCoCrFeNi_(2.1)EHEA primarily consists of order BCC(B2)and face-centered-cubic(FCC)phases,while the AlCoCrFeNi_(2.1)-x NbC(x=2.5wt%,5.0wt%,7.5wt%,and 10wt%)HEAs are composed of B2,FCC,and NbC *** the increase of milling time,the powder goes through three stages,irregularity,cold welding fracture and *** particle size of AlCoCrFeNi_(2.1)EHEA powder shows a trend of first increasing and then ***,the particle size presents a normal distribution during 0-50 h *** the addition of NbC,the AlCoCrFeNi_(2.1)-x NbC HEAs powders are significantly *** the degree of grain refinement gradually increases with the increase of NbC content.

关键词： utectic high entropy alloy mechanical alloying alloying behavior grain size

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Interface engineering by redox reaction on ferrites to prepare efficient electromagnetic wave absorbers

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Journal of materials science & Technology 2024年第21期188卷 1-10页

作者： Ming Qin Qianxu Ye Xiaoming Cai Jinming Cai Hongjing Wu Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China Faculty of Mechanical and Electrical Engineering Kunming University of Science and TechnologyKunming 650500China MOE Key Laboratory of Material Physics and Chemistry Under Extraordinary School of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi’an 710072China Southwest United Graduate School Kunming 650092China

Preparation of electromagnetic(EM)wave-absorbing composites by interface engineering has been the main strategy to obtain high-performance ***,the conventional strategy is tedious and time-consuming,which hinders the scalable synthesis of stable EM wave-absorbing ***,interface engineering by a redox reaction between transition metal elements in Co-based spinel ferrites was employed to create EM wave-absorbing composites to solve the above *** serial M Co_(2)O_(4)(M=Ni,Cu,and Zn)spinel ferrites,redox reactions during synthesis only occurred between Cu and Co elements,thus leading to the presence of multiple crystal phases on final *** the aid of increased polyethylene glycol(PEG)molecular weight(MW),more heterogenous interfaces between CuO and CuCo_(2)O_(4)phases as well as induced crystal defects were *** synergetic interface engineering by means of PEG-assisted redox reaction,interfacial polarization,and defect-induced polarization loss were markedly enhanced on a CuCo_(2)O_(4)-based sample that was prepared with PEG MW of 100 *** effective absorption bandwidth of the corresponding sample could reach 6.48 GHz(11.52–18 GHz)with a thickness of 2.28 *** short,this work provides a novel strategy for designing EM wave absorbing composites by interface engineering through redox reaction instead of the conventional composition coupling process.

关键词： Electromagnetic wave absorption Redox reaction Interfacial engineering Spinel ferrite

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Wear Properties of Spark Plasma‑Sintered AlCoCrFeNi2.1 Eutectic High Entropy Alloy with NbC Additions

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Acta Metallurgica Sinica(English Letters) 2023年第6期36卷 987-998页

作者： Hui Jiang Li Li Jianming Wang Chengbin Wei Qiang Zhang Chunjian Su Huaiming Sui College of Mechanical and Electronic Engineering Shandong University of Science and TechnologyQingdao 266590China College of Electromechanical Engineering Qingdao University of Science&TechnologyQingdao 266061China Yangzhou Fengming Photoelectric New Material Co.Ltd Yangzhou 225000China

AlCoCrFeNi_(2.1-x)NbC(x=0,2.5,7.5,and 10 wt%,denoted as NbC0,NbC2.5,NbC7.5,and NbC10)high-entropy alloy(HEA)matrix composites were fabricated by mechanical alloying(MA)and spark plasma sintering(SPS)*** effect of NbC content on the microstructures,Vickers hardness,and wear properties of AlCoCrFeNi_(2.1) eutectic high entropy alloy(EHEA)was systematically *** results indicate that the AlCoCrFeNi_(2.1) alloy consisted of FCC,B2,Al_(2)O_(3),and Cr_(7)C_(3) phases,while the AlCoCrFeNi_(2.1-x)NbC(x>0)alloys consisted of FCC,NbC,Al_(2)O_(3),and Cr_(7)C_(3) *** AlCoCrFeNi_(2.1-x)NbC alloys exhibit excellent Vickers hardness with 679 HV,664 HV,677 HV,and 695 HV,*** addition,with the addition of NbC,the average friction coefficient and wear rate of the AlCoCrFeNi_(2.1)-xNbC alloys decrease from 0.59 to 0.42 and from 1.5.10–5 mm^(3) N^(−1) m^(−1) to 2.4.10–6 mm^(3) N^(−1) m^(−1),***,NbC10 alloy shows the smallest average friction coefficient of 0.42 and lowest wear rate of 2.4.10–6 mm^(3) N^(−1) m^(−1),indicating that the NbC10 alloy displays the best wear *** the wear mechanism of the NbC10 alloy was oxidation wear accompanied by slight adhesive wear.

关键词： Eutectic High entropy alloy Microstructures Vickers hardness Wear property

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Characterization of H2-air detonations with high-speed (2.5 MHz) Rayleigh scattering and single-shot planar laser-induced fluorescence of nitric oxide

Characterization of H2-air detonations with high-speed (2.5 ...

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AIAA science and Technology Forum and Exposition, AIAA SciTech Forum 2025

作者： Chatelain, Karl P. Alicherif, Mhedine Guiberti, Thibault F. Lacoste, Deanna A. Mechanical Engineering Program Physical Science and Engineering Division PO box 4700 Thuwal23955-6900 Saudi Arabia

ISBN: (纸本)9781624107238

This study characterizes a CJ hydrogen-air detonation using high-speed Rayleigh scattering and single-shot planar laser-induced fluorescence of nitric oxide (NO-PLIF). Firstly, we demonstrate that a Nd:YAG laser cluster can be employed to conduct high-speed Rayleigh scattering visualizations of hydrogen-air detonations at 25 kPa, achieving effective visualization frequencies of 2.5MHz in this study. This multipulse Rayleigh scattering diagnostic is complementary to the existing techniques: (i) it enables the characterization of any detonation, from CJ detonations in large aspect ratio channel to marginal detonations in narrow channels;(ii) it is significantly less expensive than typical burst-mode lasers;(iii) it has adjustable visualization frequency, which can go beyond 10MHz with the same energy per pulse. This makes this diagnostic even more suitable for high-pressure detonations or for undiluted conditions, where structures are smaller and detonations faster, respectively;(iv) it is easily applicable to higher initial pressures since the Rayleigh signal scales with number density. Secondly, we combine this multipulse Rayleigh scattering with NO-PLIF to complement the average speed and speed decay measurements with local induction zone length (δi) measurements. This five-beam configuration provides measurement capabilities similar to our previous three beam configuration, outside of the local speed decay. Furthermore, an experimental and numerical assessment reveals that δi measurements cannot be achieved from Rayleigh scattering, as they are significantly underestimated—by approximately 25%—compared to those from NO-PLIF. Hence, NO-PLIF is recommended over Rayleigh scattering for accurate δi measurements in future studies. © 2025, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Rayleigh scattering

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