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Modelling of grinding mechanics:A review

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Chinese Journal of Aeronautics 2023年第7期36卷 25-39页

作者： Qingyu MENG Bing GUO Qingliang Zhao hao nan li Mark JJACKSON Barbara SliNKE Xichun LUO Center for Precision Engineering School of Mechatronics EngineeringHarbin Institute of TechnologyHarbin 150001China School of Aerospace The University of Nottingham NingboNingbo 315100China School of Integrated Studies College of Technology and AviationKansas State UniversitySalinaKS 67401USA Department of Mechanical and Aerospace Engineering University of California DavisDavisUSA Centre for Precision Manufacturing DMEMUniversity of StrathclydeGlasgowUK

Grinding is one of the most widely used material removal methods at the end of many process *** force is related to almost all grinding parameters,which has a great influence on material removal rate,dimensional and shape accuracy,surface and subsurface integrity,thermodynamics,dynamics,wheel durability,and machining system *** that grinding force is related to almost all grinding parameters,grinding force can be used to detect grinding wheel wear,energy calculation,chatter suppression,force control and grinding process *** prediction of grinding forces is important for optimizing grinding parameters and the structure of grinding machines and *** there are substantial research papers on grinding mechanics,a comprehensive review on the modeling of grinding mechanics is still absent from the *** fill this gap,this work reviews and introduces theoretical methods and applications of mechanics in grinding from the aspects of modeling principles,limitations and possible future trendencies.

关键词： Force modeling Grinding Grinding mechanics Macro force Micro force Model application

Janus Poly(Vinylidene Fluoride)Membranes with Penetrative Pores for Photothermal Desalination

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Research 2020年第1期2020卷 534-544页

作者： hao-hao Yu lin-Jiong Yan Ye-Cheng Shen Si-Yu Chen hao-nan li Jing Yang Zhi-Kang Xu MOE Key Laboratory of Macromolecular Synthesis and Functionalization and Key Laboratory of Adsorption and Separation Materials&Technologies of Zhejiang ProvinceDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

Solar-driven desalination has been considered as a promising technology for producing clean water through an abundant and pollution-free energy *** is a critical challenge to reasonably design the porous morphology and the thermal management of photothermal membranes for enabling efficient energy conversion and water *** this work,a Janus poly(vinylidene fluoride)membrane was fabricated in combination of penetrative pore structure,asymmetric surface wettability with proper thermal management for high-efficiency solar *** open and directly penetrative pores achieved by the two-dimensional solvent freezing strategy are considered to provide direct pathways for water and vapor *** unique feature of hydrophobic upper layer/hydrophilic lower layer enables the photothermal membranes to self-float on the water surface and rapidly pump water from the bulk to the *** resulting Janus membrane exhibits a satisfactory light absorbance as high as 97%and a photothermal conversion efficiency of 62.8%under one-sun irradiation in a direct contact *** solar-to-vapor efficiency rises up to 90.2%with the assistance of a thermal insulator adopted *** the Janus membrane and the composite setup are able to work efficiently with a high stability in seawater desalination,and the concentration of ion in condensed water is reduced to below 1 ***,Janus membranes with directly penetrative pores and photothermal surfaces shine a light on the development of high-performance solar evaporators for the practical application in solar seawater desalination.

关键词： composite thermal pores

Fiber-reinforced composites in milling and grinding:machining bottlenecks and advanced strategies

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Frontiers of Mechanical Engineering 2022年第2期17卷 1-35页

作者： Teng GAO Yanbin ZHANG Changhe li Yiqi WANG Yun CHEN Qinglong AN Song ZHANG hao nan li Huajun CAO Hafiz Muhammad Ali Zongming ZHOU Shubham SHARMA School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266520China School of Mechanical Engineering Dalian University of TechnologyDalian 116024China Chengdu Tool Research Institute Co. Ltd.Chengdu 610500China School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Mechanical Engineering Shandong UniversityJinan 250061China School of Aerospace University of Nottingham Ningbo ChinaNingbo 315100China School of Mechanical Engineering Chongqing UniversityChongqing 400044China Mechanical Engineering Department King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia Hanergy(Qingdao)Lubrication Technology Co. Ltd.Qingdao 266100China Department of Mechanical Engineering IK Gujral Punjab Technical UniversityPunjab 144603India

Fiber-reinforced composites have become the preferred material in the fields of aviation and aerospace because of their high-strength performance in unit *** composite components are manufactured by near netshape and only require finishing operations to achieve final dimensional and assembly *** and grinding arise as the preferred choices because of their precision ***,given their laminated,anisotropic,and heterogeneous nature,these materials are considered *** undesirable results and challenging breakthroughs,the surface damage and integrity of these materials is a research hotspot with important engineering *** review summarizes an up-to-date progress of the damage formation mechanisms and suppression strategies in milling and grinding for the fiber-reinforced composites reported in the ***,the formation mechanisms of milling damage,including delamination,burr,and tear,are ***,the grinding mechanisms,covering material removal mechanism,thermal mechanical behavior,surface integrity,and damage,are ***,suppression strategies are reviewed systematically from the aspects of advanced cutting tools and technologies,including ultrasonic vibration-assisted machining,cryogenic cooling,minimum quantity lubrication(MQL),and tool optimization *** vibration shows the greatest advantage of restraining machining force,which can be reduced by approximately 60%compared with conventional *** cooling is the most effective method to reduce temperature with a maximum reduction of approximately 60%.MQL shows its advantages in terms of reducing friction coefficient,force,temperature,and tool ***,research gaps and future exploration directions are prospected,giving researchers opportunity to deepen specific aspects and explore new area for achieving high precision surface machining of fiber-reinforced composites.

关键词： milling grinding fiber-reinforced composites damage formation mechanism delamination material removal mechanism surface integrity minimum quantity lubrication

Martensite decomposition under thermal-mechanical coupling conditions to fabricate an ultrafine-grained Ti6Al4Mo4Zr1W0.2Si alloy

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Journal of Materials Science & Technology 2024年第1期168卷 157-168页

作者： Taoyu Zhou Jiuxu Yang nan li hao Sun Bohua Zhang Zibo Zhao Qingjiang Wang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

The fabrication of ultrafine-grained microstructures(grain size below 1μm)in titanium alloys is beneficial for improving their mechanical properties at room temperature and medium tempera-tures(400-550°C).However,a long-standing challenge involves the low-cost manufacturing of bulk ultrafine-grained titanium *** this work,we developed a facile strategy through martensite de-composition at thermal-mechanical coupling conditions,to fabricate an equiaxed microstructure in a Ti6Al4Mo4Zr1W0.2Si model alloy with an averageαgrain size of 315±62 *** formation of the ultrafine-grained microstructure was because the lattice strain stored in the martensitic initial mi-crostructure enhanced the nucleation rate of dynamic recrystallization,meanwhile,the pinning role of martensite decomposition productsβand(Ti,Zr)_(5)Si_(3)phases suppressed grain coarsening at high *** to conventional(α+β)alloys,the tensile strength of this alloy improved by 20%-30%at both room temperature and 550°C,without decreasing its *** situ SEM observations revealed that the ultrafine-grained microstructure would not only suppress dislocation motions but also contribute to the homogenous deformation in the matrix of the material,therefore,it resulted in higher mechanical *** research results may be of great significance to the development of next-generation aviation titanium alloys.

关键词： Ultrafine-grained Titanium alloy In situ observation Deformation mechanism Thermostability

Optimal geometrical configuration and oxidation state of cobalt cations in spinel oxides to promote the performance of li-O_(2) battery

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nano Research 2024年第1期17卷 221-227页

作者： Yu Zhang Shuting Zhang Mengwei Yuan Yufeng li Rong liu Caiyun nan Chen Chen Engineering Research Center of Advanced Rare Earth Materials Department of ChemistryTsinghua UniversityBeijing 100084China Beijing Key Laboratory of Energy Conversion and Storage Materials Institution College of ChemistryBeijing Normal UniversityBeijing 100875China X-ray diffraction Lab Analytical and Testing CenterBeijing Normal UniversityBeijing 100875China

Co_(3)O_(4) is considered as one of promising cathode catalysts for lithium oxygen(li-O_(2))batteries,which contains both tetrahedral Co^(2+)sites(Co^(2+)Td)and octahedral Co^(3+)sites(Co^(3+)Oh).It is important to reveal the effect of optimal geometric configuration and oxidation state of cobalt ion in Co_(3)O_(4) to improve the performance of li-O_(2) ***,through regulating the synthesis process,Co^(2+)and Co^(3+)sites in Co_(3)O_(4) were replaced with Zn and Al atoms to form materials with a unique Co *** li-O_(2) batteries based on ZnCo_(2)O_(4) showed longer cycle life than that of CoAl_(2)O_(4),suggesting that in Co_(3)O_(4),the Co^(3+)Oh site is a relatively better geometric configuration than Co^(2+)Td site for li-O_(2) *** calculations revealed that Co^(3+)Oh sites provide higher catalysis activity,regulating the adsorption energy of the intermediate liO_(2) and accelerating the kinetics of the reaction in batteries,which further leads to the change of the morphology of the discharge product and ultimately improves the electrochemical performance of the batteries.

关键词： lithium oxygen(li-O_(2))batteries geometrical configuration oxidation state lithium peroxide

The swirl and pyrolysis reaction synergistically enhance solid-solid heat transfer and product separation in cyclone pyrolyzer Author links open overlay panel

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Particuology 2024年第8期91卷 118-127页

作者： haorui Niu Jingxuan Yang Wenhao lian nan Zhang Yongguo li Hongzheng Ren Xiaogang hao Guoqing Guan College of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan030024 China School of Chemical Engineering and Technology North University of ChinaTaiyuan030051 China CNNC Key Laboratory on Radioactive Gas Purification Technology China Institute for Radiation ProtectionTaiyuan030006 China Energy Conversion Engineering Laboratory Institute of Regional InnovationHirosaki University3-BunkyochoHirosaki036-8561Japan

Cyclone pyrolyzer is a novel type of downer that combines centrifugal force field and double-layer cyclone *** on transfer behavior is helpful to optimize the pyrolyzer to meet the needs of *** this study,the Computational Particle Fluid Dynamics(CPFD)model is used to analyze the transfer behavior of binary particles,and finds that the swirl and reaction have a synergistic *** effect can increase the heating rate of the particles to the range of flash pyrolysis,and its mechanism lies in the flow field structure of the *** to the centrifugal force field,the particles gather to the near *** rapid swirl,which facilitates intense gas-solid heat transfer,leads to the rapid heating and pyrolysis of biomass *** the pyrolysis proceeds,the mass of the biomass particles becomes smaller and they are more easily affected by the gas flow in *** the action of gas flow,char particles serve as new heat carrier to form the inner cycle of particles,which strengthens the heating *** pyrolysis products are discharged from the exhaust port in time with the flow field of the pyrolyzer to achieve separation from the heat carrier and inhibit the occurrence of secondary reactions.

关键词： Biomass pyrolysis Cyclone pyrolyzer Intra-particle circulation Synergistic effect

New insights into the pre-lithiation kinetics of single-crystalline Ni-rich cathodes for long-life li-ion batteries

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Green Energy & Environment 2024年第3期9卷 556-564页

作者： Qiang Han Lele Cai Zhaofeng Yang Yanjie Hu hao Jiang Chunzhong li Shanghai Engineering Research Center of Hierarchical nanomaterials School of Chemical EngineeringEast China University of Science and TechnologyShanghai200237China Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai200237China

Developing single-crystalline Ni-rich cathodes is an effective strategy to improve the safety and cycle life of li-ion batteries(liBs).However,the easy-to-loss of li and O in high-temperature lithiation results in unsatisfactory ordered layered structure and ***,we demonstrate the synthesis of highly-ordered and fully-stoichiometric single-crystalline liNi_(0.83)Co_(0.12)Mn_(0.05)O_(2)(SC-NCM83)cathodes by the regulation of pre-lithiation *** well-balanced pre-lithiation kinetics have been proved to greatly improve the proportion of layered phase in the intermediate by inhibiting the formation of metastable spinel phase,which promoted the rapid transformation of the intermediate into highly-ordered layered SC-NCM83 in the subsequent lithiation *** coating a layer of li_(2)O–B_(2)O_(3),the resultant cathodes deliver superior cycling stability with 90.9%capacity retention at 1C after 300 cycles in pouch-type full *** enhancement mechanism has also been *** findings exhibit fundamental insights into the pre-lithiation kinetics process for guiding the synthesis of high-quality singlecrystalline Ni-rich cathodes.

关键词： Single-crystalline cathode Ni-rich oxides Pre-lithiation li-ion batteries Surface modification

A highly sensitive multiple-mode optical thermometer designed in Eu^(2+/3+)and li^(+)co-doped polymorphism compound LaSc_(3)(BO_(3))_(4)

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Journal of Advanced Ceramics 2024年第6期13卷 821-833页

作者： nan Yang Zhuo li Tingxia Zhou Ziwang Zhang Wen Shi Yexiang Tong Jianxin Shi School of Chemistry IGCMESun Yat-sen UniversityGuangzhou 510006China MOE of the Key Laboratory of Bioinorganic and Synthetic Chemistry IGCMEThe Key Lab of Low-Carbon Chemistry&Energy Conservation of Guangdong ProvinceSun Yat-sen UniversityGuangzhou 510006China

Noncontact optical thermometers have attracted widespread attention,but existing problems such as single-mode and low-sensitivity thermometers still urgently need to be ***,a novel multiple-mode thermometer was designed for the polymorphism LaSc_(3)(BO_(3))_(4):Eu^(2+/3+),li^(+).X-ray diffraction(XRD)patterns revealed a slight transition betweenα-andβ-phases with the concentrations of the dopants,which is further proved by structure refinements and first-principles *** coexistence of Eu^(2+)and Eu^(3+)in the phosphors and their relative percentages were confirmed by X-ray absorption near-edge structure(XANES)*** from appropriate emissions from Eu^(2+)and Eu^(3+)without obvious energy transfer and their opposite changing trends with temperatures under 307 nm excitation,a triple-mode optical thermometer is obtained for this material within the temperature range of 150–450 *** highest sensitivities of 27.65,14.05,and 7.68%·K^(−1)are achieved based on two fluorescence intensity ratio(FIR)modes of Eu^(2+)and Eu^(3+)(5d–4f/^(5)D_(0)–^(7)F_(2,4))and the fluorescence lifetime(FL)mode of Eu^(2+),*** the best of our knowledge,the former is almost the highest in Eu^(2+)and Eu^(3+)co-doped *** results indicate that this material may be used as an excellent multiple-mode optical thermometer.

关键词： phase transition europium(Eu)ions multiple-mode optical thermometer thermal quenching properties fluorescence intensity ratio(FIR) fluorescence lifetime(FL)

Coupling interface constructions of hollow Co-Mo mixed multiple oxidation states heterostructure for high-performance aprotic li-O_(2) battery

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nano Research 2024年第5期17卷 4100-4107页

作者： Xingzi Zheng Mengwei Yuan Jingshen Xu Zihan li Caiyun nan Genban Sun Beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal UniversityBeijing 100875China Center for Advanced Materials Research Beijing Normal UniversityZhuhai 519087China

Constructing interfaces in heterostructures is effective for modulating the electronic properties of *** hollow CoMoO_(4)-Co_(3)O_(4) heterostructure(HCMCH)was prepared as a bifunctional electrocatalyst for li-O_(2) *** different components in CoMoO_(4)-Co_(3)O_(4) heterostructure presented the efficient coupling and enhanced the electrocatalytic activity for aprotic oxygen reduction reaction(ORR)and oxygen evolution reaction(OER),in which it improved the obviously reduced overpotential of 300 mV(compared with the pure Ketjen black(KB)electrode),enhanced reversibility of 80%capacity retention after 6 full cycles and the superior cyclability of more than 200 cycles with an optimized *** battery performance of the HCMCH was not only associated with the unique hollow structure and rich active sites but also with coupling interface constructions synergetic effects attaching to the improving conductivity and optimized the discharge *** results suggested that this HCMCH electrocatalyst was a promising candidate for the li-O_(2) battery and it gave a novel insight for high performance electrocatalyst designing.

关键词： li-oxygen battery heterostructure electrocatalyst coupling interface