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Experimental Study on Titanium Alloy Cutting Property and Wear Mechanism with Circular-arc Milling Cutters 被引量:2
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作者 Tao Chen Jiaqiang Liu +3 位作者 Gang Liu Hui Xiao Chunhui Li Xianli Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第3期219-229,共11页
Titanium alloy has been applied in the field of aerospace manufacturing for its high specific strength and hardness.Nonetheless,these properties also cause general problems in the machining,such as processing ineffici... Titanium alloy has been applied in the field of aerospace manufacturing for its high specific strength and hardness.Nonetheless,these properties also cause general problems in the machining,such as processing inefficiency,serious wear,poor workpiece face quality,etc.Aiming at the above problems,this paper carried out a comparative experimental study on titanium alloy milling based on the CAMCand BEMC.The variation law of cutting force and wear morphology of the two tools were obtained,and the wear mechanism and the effect of wear on machining quality were analyzed.The conclusion is that in contrast with BEMC,under the action of cutting thickness thinning mechanism,the force of CAMC was less,and its fluctuation was more stable.The flank wear was uniform and near the cutting edge,and the wear rate was slower.In the early period,the wear mechanism of CAMC was mainly adhesion.Gradually,oxidative wear also occurred with milling.Furthermore,the surface residual height of CAMC was lower.There is no obvious peak and trough accompanied by fewer surface defects. 展开更多
关键词 Circular-arc milling cutter titanium alloy Ball-end milling cutter Surface quality milling force Tool wear Machining quality
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Tribological Behaviors of Electroless Nickel-Boron Coating on Titanium Alloy Surface
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作者 Yao Jia Jianping Lai +3 位作者 Jiaxin Yu Huimin Qi Yafeng Zhang Hongtu He 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第1期309-320,共12页
Titanium alloys are excellent structural materials in engineering fields,but their poor tribological properties limit their further applications.Electroless plating is an effective method to enhance the tribological p... Titanium alloys are excellent structural materials in engineering fields,but their poor tribological properties limit their further applications.Electroless plating is an effective method to enhance the tribological performance of alloys,but it is difficult to efficiently apply to titanium alloys,due to titanium alloy’s strong chemical activity.In this work,the electroless Nickel-Boron(Ni-B)coating was successfully deposited on the surface of titanium alloy(Ti-6AL-4V)via a new pre-treatment process.Then,linearly reciprocating sliding wear tests were performed to evaluate the tribological behaviors of titanium alloy and its electroless Ni-B coatings.It was found that the Ni-B coatings can decrease the wear rate of the titanium alloy from 19.89×10^(−3)mm^(3)to 0.41×10^(−3)mm^(3),which attributes to the much higher hardness of Ni-B coatings.After heat treatment,the hardness of Ni-B coating further increases corresponding to coating crystallization and hard phase formation.However,heat treatment does not improve the tribological performance of Ni-B coating,due to the fact that higher brittleness and more severe oxidative wear exacerbate the damage of heat-treated coatings.Furthermore,the Ni-B coatings heat-treated both in air and nitrogen almost present the same tribological performance.The finding of this work on electroless coating would further extend the practical applications of titanium alloys in the engineering fields. 展开更多
关键词 Electroless coating titanium alloy TRIBOLOGY WEAR Heat treatment NANOINDENTATION
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Effect of titanium on the sticking of pellets based on hydrogen metallurgy shaft furnace:Behavior analysis and mechanism evolution
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作者 Jinge Feng Jue Tang +4 位作者 Zichuan Zhao Mansheng Chu Aijun Zheng Xiaobing Li Xiao’ai Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期282-291,共10页
Direct reduction based on hydrogen metallurgical gas-based shaft furnace is a promising technology for the efficient and low-carbon smelting of vanadium-titanium magnetite.However,in this process,the sticking of pelle... Direct reduction based on hydrogen metallurgical gas-based shaft furnace is a promising technology for the efficient and low-carbon smelting of vanadium-titanium magnetite.However,in this process,the sticking of pellets occurs due to the aggregation of metal-lic iron between the contact surfaces of adjacent pellets and has a serious negative effect on the continuous operation.This paper presents a detailed experimental study of the effect of TiO2 on the sticking behavior of pellets during direct reduction under different conditions.Results showed that the sticking index(SI)decreased linearly with the increasing TiO2 addition.This phenomenon can be attributed to the increase in unreduced FeTiO3 during reduction,leading to a decrease in the number and strength of metallic iron interconnections at the sticking interface.When the TiO2 addition amount was raised from 0 to 15wt%at 1100°C,the SI also increased from 0.71%to 59.91%.The connection of the slag phase could be attributed to the sticking at a low reduction temperature,corresponding to the low sticking strength.Moreover,the interconnection of metallic iron became the dominant factor,and the SI increased sharply with the increase in re-duction temperature.TiO2 had a greater effect on SI at a high reduction temperature than at a low reduction temperature. 展开更多
关键词 titanium sticking index hydrogen metallurgy direct reduction PELLETS
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Tuning the crystallinity of titanium nitride on copper-embedded carbon nanofiber interlayers for accelerated electrochemical kinetics in lithium-sulfur batteries
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作者 Yinyu Xiang Liqiang Lu +4 位作者 Feng Yan Debarun Sengupta Petra Rudolf Ajay Giri Prakash Kottapalli Yutao Pei 《Carbon Energy》 SCIE EI CAS CSCD 2024年第6期40-55,共16页
The development of lithium-sulfur(Li-S)batteries is hindered by the disadvantages of shuttling of polysulfides and the sluggish redox kinetics of the conversion of sulfur species during discharge and charge.Herein,the... The development of lithium-sulfur(Li-S)batteries is hindered by the disadvantages of shuttling of polysulfides and the sluggish redox kinetics of the conversion of sulfur species during discharge and charge.Herein,the crystallinities of a titanium nitride(TiN)film on copper-embedded carbon nanofibers(Cu-CNFs)are regulated and the nanofibers are used as interlayers to resolve the aforementioned crucial issues.A low-crystalline TiN-coated Cu-CNF(L-TiN-Cu-CNF)interlayer is compared with its highly crystalline counterpart(H-TiN-Cu-CNFs).It is demonstrated that the L-TiN coating not only strengthens the chemical adsorption toward polysulfides but also greatly accelerates the electrochemical conversion of polysulfides.Due to robust carbon frameworks and enhanced kinetics,impressive highrate performance at 2 C(913 mAh g^(-1)based on sulfur)as well as remarkable cyclic stability up to 300 cycles(626 mAh g^(-1))with capacity retention of 46.5%is realized for L-TiN-Cu-CNF interlayer-configured Li-S batteries.Even under high loading(3.8 mg cm^(-2))of sulfur and relatively lean electrolyte(10μL electrolyte per milligram sulfur)conditions,the Li-S battery equipped with L-TiN-Cu-CNF interlayers delivers a high capacity of 1144 mAh g^(-1)with cathodic capacity of 4.25 mAh cm^(-2)at 0.1 C,providing a potential pathway toward the design of multifunctional interlayers for highly efficient Li-S batteries. 展开更多
关键词 CRYSTALLINITY electrochemical kinetics INTERLAYER lithium-sulfur batteries titanium nitride
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Integrated high-performance and accurate shaping technology of low-cost powder metallurgy titanium alloys: A comprehensive review
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作者 Xuemeng Gan Shaofu Li +1 位作者 Shunyuan Xiao Yafeng Yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期413-426,共14页
The practical engineering applications of powder metallurgy (PM) Ti alloys produced through cold compaction and pressure-less sintering are impeded by poor sintering densification, embrittlement caused by excessive O ... The practical engineering applications of powder metallurgy (PM) Ti alloys produced through cold compaction and pressure-less sintering are impeded by poor sintering densification, embrittlement caused by excessive O impurities, and severe sintering deforma-tion resulting from the use of heterogeneous powder mixtures. This review presents a summary of our previous work on addressing the above challenges. Initially, we proposed a novel strategy using reaction-induced liquid phases to enhance sintering densification. Near- complete density (relative density exceeding 99%) was achieved by applying the above strategy and newly developed sintering aids. By focusing on the O-induced embrittlement issue, we determined the onset dissolution temperature of oxide films in the Ti matrix. On the basis of this finding, we established a design criterion for effective O scavengers that require reaction with oxide films before their dissol-ution. Consequently, a ductile PM Ti alloy was successfully obtained by introducing 0.3wt% NdB6 as the O scavenger. Lastly, a powder- coating strategy was adopted to address the sintering deformation issue. The ultrafine size and shell-like distribution characteristics of coating particles ensured rapid dissolution and homogeneity in the Ti matrix, thereby facilitating linear shrinkage during sintering. As a result, geometrically complex Ti alloy parts with high dimensional accuracy were fabricated by using the coated powder. Our fundament-al findings and related technical achievements enabled the development of an integrated production technology for the high-performance and accurate shaping of low-cost PM Ti alloys. Additionally, the primary engineering applications and progress in the industrialization practice of our developed technology are introduced in this review. 展开更多
关键词 powder metallurgy titanium sintering densification oxygen scavenging accurate shaping
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Growth kinetics of titanium carbide coating by molten salt synthesis process on graphite sheet surface
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作者 Xiaoyu Shi Chongxiao Guo +4 位作者 Jiamiao Ni Songsong Yao Liqiang Wang Yue Liu Tongxiang Fan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第8期1858-1864,共7页
The synthesis of carbide coatings on graphite substrates using molten salt synthesis(MSS),has garnered significant interest due to its cost-effective nature.This study investigates the reaction process and growth kine... The synthesis of carbide coatings on graphite substrates using molten salt synthesis(MSS),has garnered significant interest due to its cost-effective nature.This study investigates the reaction process and growth kinetics involved in MSS,shedding light on key aspects of the process.The involvement of Ti powder through liquid-phase mass transfer is revealed,where the diffusion distance and quantity of Ti powder play a crucial role in determining the reaction rate by influencing the C content gradient on both sides of the carbide.Furthermore,the growth kinetics of the carbide coating are predominantly governed by the diffusion behavior of C within the carbide layer,rather than the chemical reaction rate.To analyze the kinetics,the thickness of the carbide layer is measured with respect to heat treatment time and temperature,unveiling a parabolic relationship within the temperature range of 700-1300℃.The estimated activation energy for the reaction is determined to be 179283 J·mol^(-1).These findings offer valuable insights into the synthesis of carbide coatings via MSS,facilitating their optimization and enhancing our understanding of their growth mechanisms and properties for various applications. 展开更多
关键词 titanium carbide GRAPHITE molten salt kinetic analysis
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Elimination of methicillin‑resistant Staphylococcus aureus biofilms on titanium implants via photothermally‑triggered nitric oxide and immunotherapy for enhanced osseointegration
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作者 Yong‑Lin Yu Jun‑Jie Wu +5 位作者 Chuan‑Chuan Lin Xian Qin Franklin R.Tay Li Miao Bai‑Long Tao Yang Jiao 《Military Medical Research》 SCIE CAS CSCD 2024年第2期157-179,共23页
Background:Treatment of methicillin-resistant Staphylococcus aureus(MRSA)biofilm infections in implant placement surgery is limited by the lack of antimicrobial activity of titanium(Ti)implants.There is a need to expl... Background:Treatment of methicillin-resistant Staphylococcus aureus(MRSA)biofilm infections in implant placement surgery is limited by the lack of antimicrobial activity of titanium(Ti)implants.There is a need to explore more effective approaches for the treatment of MRSA biofilm infections.Methods:Herein,an interfacial functionalization strategy is proposed by the integration of mesoporous polydopamine nanoparticles(PDA),nitric oxide(NO)release donor sodium nitroprusside(SNP)and osteogenic growth peptide(OGP)onto Ti implants,denoted as Ti-PDA@SNP-OGP.The physical and chemical properties of Ti-PDA@SNP-OGP were assessed by scanning electron microscopy,X-ray photoelectron spectroscope,water contact angle,photothermal property and NO release behavior.The synergistic antibacterial effect and elimination of the MRSA biofilms were evaluated by 2′,7′-dichlorofluorescein diacetate probe,1-N-phenylnaphthylamine assay,adenosine triphosphate intensity,O-nitrophenyl-β-D-galactopyranoside hydrolysis activity,bicinchoninic acid leakage.Fluorescence staining,assays for alkaline phosphatase activity,collagen secretion and extracellular matrix mineralization,quantitative real‑time reverse transcription‑polymerase chain reaction,and enzyme-linked immunosorbent assay(ELISA)were used to evaluate the inflammatory response and osteogenic ability in bone marrow stromal cells(MSCs),RAW264.7 cells and their co-culture system.Giemsa staining,ELISA,micro-CT,hematoxylin and eosin,Masson's trichrome and immunohistochemistry staining were used to evaluate the eradication of MRSA biofilms,inhibition of inflammatory response,and promotion of osseointegration of Ti-PDA@SNP-OGP in vivo.Results:Ti-PDA@SNP-OGP displayed a synergistic photothermal and NO-dependent antibacterial effect against MRSA following near-infrared light(NIR)irradiation,and effectively eliminated the formed MRSA biofilms by inducing reactive oxygen species(ROS)-mediated oxidative stress,destroying bacterial membrane integrity and causing leakage of intracellular components(P<0.01).In vitro experiments revealed that Ti-PDA@SNP-OGP not only facilitated osteogenic differentiation of MSCs,but also promoted the polarization of pro-inflammatory M1 macrophages to the anti-inflammatory M2-phenotype(P<0.05 or P<0.01).The favorable osteo-immune microenvironment further facilitated osteogenesis of MSCs and the anti-inflammation of RAW264.7 cells via multiple paracrine signaling pathways(P<0.01).In vivo evaluation confirmed the aforementioned results and revealed that Ti-PDA@SNP-OGP induced ameliorative osseointegration in an MRSA-infected femoral defect implantation model(P<0.01).Conclusions:Ti-PDA@SNP-OGP is a promising multi-functional material for the high-efficient treatment of MRSA infections in implant replacement surgeries. 展开更多
关键词 Polydopamine nanoparticles Methicillin-resistant Staphylococcus aureus Nitric oxide OSSEOINTEGRATION Osteo-immunomodulation Photothermal effect titanium implants
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Recent innovations in laser additive manufacturing of titanium alloys
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作者 Jinlong Su Fulin Jiang +8 位作者 Jie Teng Lequn Chen Ming Yan Guillermo Requena Lai-Chang Zhang Y Morris Wang Ilya V Okulov Hongmei Zhu Chaolin Tan 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第3期2-37,共36页
Titanium(Ti)alloys are widely used in high-tech fields like aerospace and biomedical engineering.Laser additive manufacturing(LAM),as an innovative technology,is the key driver for the development of Ti alloys.Despite... Titanium(Ti)alloys are widely used in high-tech fields like aerospace and biomedical engineering.Laser additive manufacturing(LAM),as an innovative technology,is the key driver for the development of Ti alloys.Despite the significant advancements in LAM of Ti alloys,there remain challenges that need further research and development efforts.To recap the potential of LAM high-performance Ti alloy,this article systematically reviews LAM Ti alloys with up-to-date information on process,materials,and properties.Several feasible solutions to advance LAM Ti alloys are reviewed,including intelligent process parameters optimization,LAM process innovation with auxiliary fields and novel Ti alloys customization for LAM.The auxiliary energy fields(e.g.thermal,acoustic,mechanical deformation and magnetic fields)can affect the melt pool dynamics and solidification behaviour during LAM of Ti alloys,altering microstructures and mechanical performances.Different kinds of novel Ti alloys customized for LAM,like peritecticα-Ti,eutectoid(α+β)-Ti,hybrid(α+β)-Ti,isomorphousβ-Ti and eutecticβ-Ti alloys are reviewed in detail.Furthermore,machine learning in accelerating the LAM process optimization and new materials development is also outlooked.This review summarizes the material properties and performance envelops and benchmarks the research achievements in LAM of Ti alloys.In addition,the perspectives and further trends in LAM of Ti alloys are also highlighted. 展开更多
关键词 additive manufacturing titanium alloys auxiliary field machine learning aerospace materials lightweight materials novel alloys
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Microstructure evolution and strengthening mechanism of high -performance powder metallurgy TA15 titanium alloy by hot rolling
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作者 Ying Gao Ce Zhang +1 位作者 Jiazhen Zhang Xin Lu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1426-1436,共11页
Hot deformation of sintered billets by powder metallurgy(PM)is an effective preparation technique for titanium alloys,which is more significant for high-alloying alloys.In this study,Ti–6.5Al–2Zr–Mo–V(TA15)titaniu... Hot deformation of sintered billets by powder metallurgy(PM)is an effective preparation technique for titanium alloys,which is more significant for high-alloying alloys.In this study,Ti–6.5Al–2Zr–Mo–V(TA15)titanium alloy plates were prepared by cold press-ing sintering combined with high-temperature hot rolling.The microstructure and mechanical properties under different process paramet-ers were investigated.Optical microscope,electron backscatter diffraction,and others were applied to characterize the microstructure evolution and mechanical properties strengthening mechanism.The results showed that the chemical compositions were uniformly dif-fused without segregation during sintering,and the closing of the matrix craters was accelerated by increasing the sintering temperature.The block was hot rolled at 1200℃ with an 80%reduction under only two passes without annealing.The strength and elongation of the plate at 20–25℃ after solution and aging were 1247 MPa and 14.0%,respectively,which were increased by 24.5%and 40.0%,respect-ively,compared with the as-sintered alloy at 1300℃.The microstructure was significantly refined by continuous dynamic recrystalliza-tion,which was completed by the rotation and dislocation absorption of the substructure surrounded by low-angle grain boundaries.After hot rolling combined with heat treatment,the strength and plasticity of PM-TA15 were significantly improved,which resulted from the dense,uniform,and fine recrystallization structure and the synergistic effect of multiple slip systems. 展开更多
关键词 elemental powder powder metallurgy titanium alloy hot rolling strength and plasticity
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Strong metal–support interaction boosts the electrocatalytic hydrogen evolution capability of Ru nanoparticles supported on titanium nitride
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作者 Xin Wang Xiaoli Yang +7 位作者 Guangxian Pei Jifa Yang Junzhe Liu Fengwang Zhao Fayi Jin Wei Jiang Haoxi Ben Lixue Zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期245-254,共10页
Ruthenium(Ru)has been regarded as one of the most promising alternatives to substitute Pt for catalyzing alkaline hydrogen evolution reaction(HER),owing to its inherent high activity and being the cheapest platinum-gr... Ruthenium(Ru)has been regarded as one of the most promising alternatives to substitute Pt for catalyzing alkaline hydrogen evolution reaction(HER),owing to its inherent high activity and being the cheapest platinum-group metal.Herein,based on the idea of strong metal–support interaction(SMSI)regulation,Ru/TiN catalysts with different degrees of TiN overlayer over Ru nanoparticles were fabricated,which were applied to the alkaline electrolytic water.Characterizations reveal that the TiN overlayer would gradually encapsulate the Ru nanoparticles and induce more electron transfer from Ru nanoparticles to TiN support by the Ru–N–Ti bond as the SMSI degree increased.Further study shows that the exposed Ru–TiN interfaces greatly promote the H_(2) desorption capacity.Thus,the Ru/TiN-300 with a moderate SMSI degree exhibits excellent HER performance,with an overpotential of 38 mV at 10 mA cm^(−2).Also,due to the encapsulation role of TiN overlayer on Ru nanoparticles,it displays super long-term stability with a very slight potential change after 24 h.This study provides a deep insight into the influence of the SMSI effect between Ru and TiN on HER and offers a novel approach for preparing efficient and stable HER electrocatalysts through SMSI engineering. 展开更多
关键词 electronic structure hydrogen evolution reaction RUTHENIUM strong metal-support interaction titanium nitride
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Comparison of electrochemical behaviors of Ti-5Al-2Sn-4Zr-4Mo-2Cr-1Fe and Ti-6Al-4V titanium alloys in NaNO_(3) solution
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作者 Jia Liu Shuanglu Duan +1 位作者 Xiaokang Yue Ningsong Qu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第4期750-763,共14页
The Ti-5Al-2Sn-4Zr-4Mo-2Cr-1Fe(β-CEZ)alloy is considered as a potential structural material in the aviation industry due to its outstanding strength and corrosion resistance.Electrochemical machining(ECM)is an effici... The Ti-5Al-2Sn-4Zr-4Mo-2Cr-1Fe(β-CEZ)alloy is considered as a potential structural material in the aviation industry due to its outstanding strength and corrosion resistance.Electrochemical machining(ECM)is an efficient and low-cost technology for manufacturing theβ-CEZ alloy.In ECM,the machining parameter selection and tool design are based on the electrochemical dissolution behavior of the materials.In this study,the electrochemical dissolution behaviors of theβ-CEZ and Ti-6Al-4V(TC4)alloys in NaNO3solution are discussed.The open circuit potential(OCP),Tafel polarization,potentiodynamic polarization,electrochemical impedance spectroscopy(EIS),and current efficiency curves of theβ-CEZ and TC4 alloys are analyzed.The results show that,compared to the TC4 alloy,the passivation film structure is denser and the charge transfer resistance in the dissolution process is greater for theβ-CEZ alloy.Moreover,the dissolved surface morphology of the two titanium-based alloys under different current densities are analyzed.Under low current densities,theβ-CEZ alloy surface comprises dissolution pits and dissolved products,while the TC4 alloy surface comprises a porous honeycomb structure.Under high current densities,the surface waviness of both the alloys improves and the TC4 alloy surface is flatter and smoother than theβ-CEZ alloy surface.Finally,the electrochemical dissolution models ofβ-CEZ and TC4 alloys are proposed. 展开更多
关键词 electrochemical machining dissolution behavior β-CEZ titanium alloy polarization curve current efficiency
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Effect of Titanium Dioxide Nanoparticles on Growth and Biomass Accumulation in Lettuce (Lactuca sativa)
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作者 Channa B. Rajashekar Brenden Armstrong 《American Journal of Plant Sciences》 CAS 2024年第1期1-13,共13页
The use of titanium dioxide nanoparticles (nTiO<sub>2</sub>) is gaining interest in agriculture because of their impact on many aspects of plant growth. The present study examines the effects of nTiO<su... The use of titanium dioxide nanoparticles (nTiO<sub>2</sub>) is gaining interest in agriculture because of their impact on many aspects of plant growth. The present study examines the effects of nTiO<sub>2</sub> (5 nm and 10 nm) applied to seeds and the seedlings as a foliar application on various aspects of growth characteristics and biomass accumulation in lettuce (Lactuca sativa, cv. Grand Rapids). Application of 10 nm nTiO<sub>2</sub> to seeds through imbibition resulted in a significant reduction in shoot biomass accumulation while 5 nm nTiO<sub>2</sub> did not affect the biomass accumulation in lettuce. The application of 10 nm nTiO<sub>2</sub> reduced the fresh shoot biomass accumulation by about 18% compared to the control plants. Other growth characteristics such as shoot dry biomass, root fresh and dry biomass, plant height, and leaf area were not affected by the application of both 5 nm and 10 nm nTiO<sub>2</sub>. In addition, foliar application of these nanoparticles to the lettuce seedlings did not have a significant effect on most of the growth parameters examined, and the increasing concentration ranging from 5 nm/L to 400 mg/L did not produce a consistent response in lettuce. Thus, nTiO<sub>2</sub> application to lettuce seeds had a notable negative impact on shoot growth while foliar application did not have a significant effect on many plant growth characteristics. However, foliar applications produced some symptoms of toxicity to the foliage in the form of necrotic or chlorotic patches on the leaves, which were more pronounced with increasing concentrations of both 5 nm and 10 nm nTiO<sub>2</sub>. However, these symptoms were apparent at a concentration as low as 50 mg/L of nTiO<sub>2</sub>. Thus, foliar application of nTiO<sub>2</sub> may not have a significant impact on many of the growth characteristics in lettuce, but it can result in foliar toxicity. 展开更多
关键词 Growth Characteristics LETTUCE NANOPARTICLES titanium Dioxide TOXICITY
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Effect of ball milling process on the microstructure of titanium-nanohydroxyapatite composite powder 被引量:1
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作者 PANG Pengsha LI Wei LIU Ying 《Rare Metals》 SCIE EI CAS CSCD 2007年第2期118-123,共6页
Titaninm-nanohydroxyapatite (Ti-nHA) composite powders, composed of titanium with 10 vol.% and 20 vol.% of nano-hydroxyapatite, were milled in a planetary ball mill using alcohol media to avoid excessive heat. XRD a... Titaninm-nanohydroxyapatite (Ti-nHA) composite powders, composed of titanium with 10 vol.% and 20 vol.% of nano-hydroxyapatite, were milled in a planetary ball mill using alcohol media to avoid excessive heat. XRD and SEM were performed for characterization of the microstructure, and the homogeneity of Ti/HA nanocomposite powder was evaluated by EPMA with prolonged ball milling time. The results show that under the condition of wet milling, the grain size of Ti-nHA composite powders is decreased with the increase in ball milling time and the amount of the addition of nHA. While for milling of 30 h, the nanocomposite powder with free structure, which consists of the nano-hydroxyapatite (nHA) particles and titanium (Ti) phase, is obtained. Three stages of milling can be observed from the dement mapping of Ti, Ca, and P by EPMA; meanwhile, it is found that the nHA would be more homogenously distributed after milling for 30 h. 展开更多
关键词 composite materials NANOCOMPOSITES mechanical milling titanium nanohydroxyapatite
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Challenges in laser-assisted milling of titanium alloys 被引量:5
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作者 Matthew S Dargusch Tharmalingam Sivarupan +3 位作者 Michael Bermingham Rizwan Abdul Rahman Rashid Suresh Palanisamy Shoujin Sun 《International Journal of Extreme Manufacturing》 EI 2021年第1期71-84,共14页
Several detailed studies have comprehensively investigated the benefits and limitations of laser-assisted machining(LAM)of titanium alloys.These studies have highlighted the positive impact of the application of laser... Several detailed studies have comprehensively investigated the benefits and limitations of laser-assisted machining(LAM)of titanium alloys.These studies have highlighted the positive impact of the application of laser preheating on reducing cutting forces and improving productivity but have also identified the detrimental effect of LAM on tool life.This paper seeks to evaluate a series of the most common cutting tools with different coating types used in the machining of titanium alloys to identify whether coating type has a dramatic effect on the dominant tool wear mechanisms active during the process.The findings provide a clear illustration that the challenges facing the application of LAM are associated with the development of new types of cutting tools which are not subjected to the diffusion-controlled wear processes that dominate the performance of current cutting tools. 展开更多
关键词 laser-assisted machining tool life tool wear titanium alloys
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PREDICTION OF SURFACE ROUGHNESS FOR END MILLING TITANIUM ALLOY USING MODIFIED PARTICLE SWARM OPTIMIZATION LS-SVM 被引量:1
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作者 刘春景 唐敦兵 +1 位作者 何华 陈兴强 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2013年第1期53-61,共9页
It is difficult to construct the prediction model for titanium alloy through analyzing the formation mechanism of surface roughness due to the complicated relation between influential factors and surface roughness.A n... It is difficult to construct the prediction model for titanium alloy through analyzing the formation mechanism of surface roughness due to the complicated relation between influential factors and surface roughness.A novel algorithm based on the modified particle swarm optimization ( PSO ) least square support vector machine ( LSSVM ) is proposed to predict the roughness of the end milling titanium alloys.According to Taguchi method and features in milling titanium alloys , the influences of cutting speed , feed rate and axial depth of cut on surface roughness are investigated with the analysis of variance ( ANOVA ) of the experimental data.The research results show that the construction speed of the modified PSO LS-SVM model is two orders of magnitude faster than that of back propagation ( BP ) model.Moreover , the prediction accuracy is about one order of magnitude higher than that of BP model.The modified PSO LS-SVM prediction model can explain the influences of cutting speed , feed rate and axial depth of cut on the surface roughness of titanium alloys.Either a higher cutting speed , a lower feed rate or a smaller axial depth of cut can lead to the decrease of surface roughness. 展开更多
关键词 titanium alloy cutting parameter surface roughness prediction modeling modified PSO LS-SVM
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Craniofacial therapy:advanced local therapies from nano-engineered titanium implants to treat craniofacial conditions 被引量:2
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作者 Karan Gulati Chengye Ding +3 位作者 Tianqi Guo Houzuo Guo Huajie Yu Yan Liu 《International Journal of Oral Science》 SCIE CAS CSCD 2023年第1期33-49,共17页
Nano-engineering-based tissue regeneration and local therapeutic delivery strategies show significant potential to reduce the health and economic burden associated with craniofacial defects,including traumas and tumou... Nano-engineering-based tissue regeneration and local therapeutic delivery strategies show significant potential to reduce the health and economic burden associated with craniofacial defects,including traumas and tumours.Critical to the success of such nano-engineered non-resorbable craniofacial implants include load-bearing functioning and survival in complex local trauma conditions.Further,race to invade between multiple cells and pathogens is an important criterion that dictates the fate of the implant.In this pioneering review,we compare the therapeutic efficacy of nano-engineered titanium-based craniofacial implants towards maximised local therapy addressing bone formation/resorption,soft-tissue integration,bacterial infection and cancers/tumours.We present the various strategies to engineer titanium-based craniofacial implants in the macro-,micro-and nano-scales,using topographical,chemical,electrochemical,biological and therapeutic modifications.A particular focus is electrochemically anodised titanium implants with controlled nanotopographies that enable tailored and enhanced bioactivity and local therapeutic release.Next,we review the clinical translation challenges associated with such implants.This review will inform the readers of the latest developments and challenges related to therapeutic nano-engineered craniofacial implants. 展开更多
关键词 IMPLANTS titanium LOCAL
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Milling Machinability of TiC Particle and TiB Whisker Hybrid Reinforced Titanium Matrix Composites 被引量:1
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作者 Huan Haixiang Xu Jiuhua +2 位作者 Su Honghua Ge Yingfei Liang Xinghui 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第4期363-371,共9页
The milling machinabilities of titanium matrix composites were comprehensively evaluated to provide a theoretical basis for cutting parameter determination.Polycrystalline diamond(PCD)tools with different grain sizes ... The milling machinabilities of titanium matrix composites were comprehensively evaluated to provide a theoretical basis for cutting parameter determination.Polycrystalline diamond(PCD)tools with different grain sizes and geometries,and carbide tools with and without coatings were used in the experiments.Milling forces,milling temperatures,tool lifetimes,tool wear,and machined surface integrities were investigated.The PCD tool required a primary cutting force 15%smaller than that of the carbide tool,while the uncoated carbide tool required a primary cutting force 10% higher than that of the TiAlN-coated tool.A cutting force of 300 Nper millimeter of the cutting edge(300N/mm)was measured.This caused excessive tool chipping.The cutting temperature of the PCD tool was 20%—30%lower than that of the carbide tool,while that of the TiAlN-coated tool was 12%lower than that of the uncoated carbide tool.The cutting temperatures produced when using water-based cooling and minimal quantity lubrication(MQL)were reduced by 100°C and 200°C,compared with those recorded with dry cutting,respectively.In general,the PCD tool lifetimes were 2—3 times longer than the carbide tool lifetimes.The roughness Raof the machined surface was less than 0.6μm,and the depth of the machined surface hardened layer was in the range of 0.15—0.25 mm for all of the PCD tools before a flank wear land of 0.2mm was reached.The PCD tool with a 0.8mm tool nose radius,0°rake angle,10°flank angle,and grain size of(30+2)μm exhibited the best cutting performance.For this specific tool,a lifetime of 16 min can be expected. 展开更多
关键词 钛基复合材料 铣削加工 TiB晶须 涂层硬质合金刀具 混杂增强 加工表面完整性 TiC PCD工具
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Tool Failure Analysis in High Speed Milling of Titanium Alloys
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作者 MEYER Kevin YU Cindy 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S1期137-142,共6页
In high speed milling of titanium alloys the high rate of tool failure is the main reason for its high manufacturing cost. In this study,fractured tools which were used in a titanium alloys 5-axis milling process have... In high speed milling of titanium alloys the high rate of tool failure is the main reason for its high manufacturing cost. In this study,fractured tools which were used in a titanium alloys 5-axis milling process have been observed both in the macro scale using a PG-1000 light microscope and in the micro scale using a Scanning Electron Microscope (SEM) respectively. These observations indicate that most of these tool fractures are the result of tool chipping. Further analysis of each chipping event has shown that beachmarks emanate from points on the cutting edge. This visual evidence indicates that the cutting edge is failing in fatigue due to cyclical mechanical and/or thermal stresses. Initial analyses explaining some of the outlying conditions for this phenomenon are discussed. Future analysis regarding determining the underlying causes of the fatigue phenomenon is then outlined. 展开更多
关键词 titanium alloys high speed millING CUTTING edge CHIPPING TOOL failure analysis
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Multi-objective Optimization in the Milling of Titanium Alloys Using the MQL Technique
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作者 艾哈迈德 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2004年第4期26-29,共4页
The process for face milling of (α+β) titanium alloy while using minimum quantity librication (MQL) as the cooling technique was optimized by using of the Taguchi method to improve characteristics.The cutting speed,... The process for face milling of (α+β) titanium alloy while using minimum quantity librication (MQL) as the cooling technique was optimized by using of the Taguchi method to improve characteristics.The cutting speed, feed rate, and depth of cut were optimized with consideration of multiple performance characteristics including tool life, volume removed and surface roughness. The experimental results show that the multiple performance characteristics can be simultaneously improved through this approach, and the feed rate is the most influential cutting parameter in the face milling of titanium alloys. 展开更多
关键词 Taguchi method millING titanium minimum quantity librication
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An Experimental Investigation on Workability and Bleeding Behaviors of Cement Pastes Doped with Nano Titanium Oxide (n-TiO 2) Nanoparticles and FlyAsh 被引量:1
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作者 FatihÇelik Oğuzhan Yıldız +1 位作者 AndaçBaturÇolak Samet Mufit Bozkır 《Fluid Dynamics & Materials Processing》 EI 2023年第1期135-158,共24页
In this study,the workability of cement-based grouts containing n-TiO 2 nanoparticles and fly ash has been investigated experimentally.Several characteristic quantities(including,but not limited to,the marsh cone flow... In this study,the workability of cement-based grouts containing n-TiO 2 nanoparticles and fly ash has been investigated experimentally.Several characteristic quantities(including,but not limited to,the marsh cone flow time,the mini slump spreading diameter and the plate cohesion meter value)have been measured for different percentages of these additives.The use of fly ash as a mineral additive has been found to result in improvements in terms of workability behavior as expected.Moreover,if nano titanium oxide is also used,an improvement can be obtained regarding the bleeding values for the cement-based grout mixes.Using such experimental data,a multi-layer perceptron artificial neural network model has been developed(5 neurons in the hidden layer of the network model have been developed using a total of 42 experimental data).70%of the data employed in this model have been used for training,15%for validation and 15%for the test phase.The results demonstrate that the artificial neural network model can predict Marsh cone flow time,mini slump spreading diameter and plate cohesion meter values with an average error of 0.15%. 展开更多
关键词 Nano titanium oxide fly ash workability of grouts BLEEDING stability of grouts ANN
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