最新刊期
卷 ， 期 4 ， 2004
- 摘要：Spray forming intergrates the advantages of rapid solidifcation and direct forming of metal materials.It is an advanced technique of material preparation,used to the manufacturing of round billets,tubes and plates with fine microstructure,homogeneous constituent distribution and highly supersaturated alloying elemenst.In order to understand the spray forming process deeply and optimize the selection of the technological parameters great attention is paid to the modeling and simulation of the spray forming process recently.The researches on the modeling and simulation of the solidification of the atomized droplets and shape evolution of the billet during spray forming were surveyed.关键词：Spray Formig;Simulation;Atomization
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发布时间：2023-12-18 - 摘要：Quasi one dimensional nanostructure materials,such as nanotubes,nanowires,nanostrip,etc.,being a burgeoning and intriguing research areas exhibited peculiar physical and chemical properties and potential application to nanodevice.The synthetic methods of quasi\|one\|dementional nano\|materials,including Vapor\|Liquid\|Solid（VLS）,Vapor\|Solid（VS）,Solution\|Liquid\|Solid（SLS）and porous Alumina Die etc,have been introduced.The forming and growth mechanism of various methods for quasi one dimensional nanostructural materials and their research trend have been reviewed.关键词：Nanostructure Materials;Nanodevice;Synthesis
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发布时间：2023-12-18 - 摘要：The development,mechanism,research details and example of cryogenic treatment were surveyed.The research achievements of cryogenic treatment have been applied to cast alloys,including high Cr cast iron,440A cast stainless steel, 45 carbon steel,in recent years.Results showed that the extremely fine alloyed carbide with dispersive distribution can strengthen high Cr cast iron and 440 A cast stainless steel with cryogenic treatment,but their wear resistance increased slightly due to the finer carbide precipitates unable to resist against abrasive machining during slide friction process with micro\|cutting.Also the effect of cryogenic treatment on the mechanical properties for 45 carbon steel was unobserved.
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发布时间：2023-12-18 -
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- 摘要：Effects of ultrasonic treatment for Al melt on microstructures and mechanical properties of 7055 Al alloy were investigated.Results showed that the activated microinclusive particulate in melt by ultrasonic cavitation can serve as the substrate for nucleation resulting in grain refinement and in turn improving greatly in tensile strength and plasticity.关键词：Ultrasonic Effect;7055 Al Alloy;Ultrasonic Vibration;Acoustic Cavitation
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发布时间：2023-12-18 - 摘要：The efects of surface stress amplitude on damping capacity of new CuAlMn shape memory alloy were examined based on tracing filter technique by measuring deamplification capacity of the alloy in the first and second resonant frequency using cantilevered bending resonant unit at a surface stress amplitude in the range of 4.05～ 40.5 MPa. It was found that the CuAlMn shape memory alloy may possess higher damping capacity in parent phase（ Q -1 max =0.12）,martensite and dual phase either.The overall damping capacity decreased with increasing in the surface stress amplitude.The damping capacity decreased faster in the alloy with parent phase than with martensite below a critical stress while decrease in damping capacity trended evenly over critical stress,slightly dependent on the microstructure.关键词：High-damping Metal;Shape Memory Alloy;Damping Capacity;CuAlMn Alloy
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发布时间：2023-12-18 -
- 摘要：The ageing behaviors of mullite short fibre reinforced Al Mg Si composites with different Mg Si ratios (Mg/Si=2.Mg/Si<2,Mg/Si> and its matrix alloy in squeezing casting were examined by means of hardness measurement （HB）,SEM,DSC and TEM.The results showed that the composites and its matrix alloy have the similar ageing hardening curves and the same precipitation procedure.Although the mullite fibre addition can improve the aged hardness and accelarate ageing hardening process of the marix alloy to some extent,the mullite fibre only silightly restrains the formation of GP zone.Excess Si or Mg not only accelarated the ageing hardening process of the composites and its matrix alloy but also obviously advanced the ageing peak of both materials.Mullite short fibre with excess Si or Mg has the interaction on ageing hardening process of the composites.关键词：Al Matrix Composites;Mullite Short Fibre;Al-Mg-Si Alloy;Ageing Behavior
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发布时间：2023-12-18 - 摘要：Effects of various minor Ce additions on microstructure and heat resistance of as cast Al 5.3Cu 0.8Mg 0.6Ag alloy have been investigated by tensile testing and TEM （transmission electron microscopy）.The results showed that the tensile strength at room temperature and heat resistance at high temperature of the as cast alloy can be improved by adding 0.20%～0.45% Ce at room temperature to 300 ℃.It is found that the Ce could refine the grain size of the alloy obviously and reduce Cu segregation in grain boundary.TEM indicated that minor Ce can refine strengthening Ω phase with increase in its precipitated density.A bulk Al x Ti 6Ce 3Cu compound appears in the as cast alloy which deteriorated sharply the tensile strength with adding both minor 0.2%Ce and 0.25%Ti.关键词：Heat Resistance Al Alloy;Ce-RE;Mechanical Properties;Microstructure
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发布时间：2023-12-18 - 摘要：Welding joint with sound microstructure and perfect bonding between the weld and AZ91B Mg base alloy can be obtained with AZ61 and AZ91 welding wire by TIG.The microstructure of the weld is composed of snowy α Mg dendrite with developed branches and interdendrite eutectic （α+Mg 17 Al 12 ） with low melting point.The microstructure of bonding zone consists of fine equaixed α Mg and interdendrite eutectic,while the microstructure of heat affected zone is very similar to those of base materials,consisting of coarse α Mg dendrites and interdendrite eutectic （α+Mg 17 Al 12 ）.Due to the super heated vaporization of Mg atom during welding,the Al content and eutectic content in the weld increase,resulting in the increase of hot crack tendency in the weld.In the case of using ERAZ61 wire,the joint consistent with base materials in composition and microstructure exhibits high crack resistance,high tensile strength and elongation.Therefore,taking comprehensive consideration for welding technology and mechanical properties of the jiont,the ER AZ61 welding wire should be selected preferably.关键词：Mg Alloy;TIG Welding;Welding Joint;Microstructure;Mechanical Property
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发布时间：2023-12-18 - 摘要：The effects of various mischmetal additions on the grain refinement of AZ91D Mg alloy were investigated.The results showed that microstructures of the AZ91D Mg alloy can be effectively refined by Ce and La additives.The Ce and La particulates in mischmetal were dispersively distributed into the Mg melt before the formation of Al RE compound and may serve as substrate for heterogeneous nucleation with 0.05% mischmetal addition.With the increase of the mischmetal addition,Ce and La prefer the formation of Al Ce and Al La compounds to be accumulated to grain boundary with the prevention of grain from growth resulting in grain refinement.
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发布时间：2023-12-18 - 摘要：Cast Al Ni Co magnetic steel LNGT72 possessed the best comprehensive magnetic property in cast magnetic steel.The conventional directional solidification in pre heated cast mold was upgraded to stably produce the castings with relatively ideal column grain and high magnetic properties under industral scale.关键词：Cast Magnetic Steel;Directional Solidification;Al-Ni-Co Alloy
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发布时间：2023-12-18 - 摘要：The micro deformation of Cu base frictional materials obtained with powder metallurgy under impact load was conducted on Hopkinson pressure bar with confined pressure and non confined pressure in the range of strain rate （10 2～10 3）/s.The impacted specimen was analyzed by SEM and X ray diffraction.The results showed that the slip dislocation was dominated in plastic deformation of the materials with defects under non confined pressure,showing the macro morphology with impact brittle damage and fracture along with grain boundary while plastic deformation was attributed to the combination of slip dislocation with turbulent pattern and twin-crystal in the matrix under confined pressure.关键词：Powder Metallurgy;Frictional Material;Impact;Slip
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发布时间：2023-12-18 - 摘要：Semi-solid thixoforming technology of AZ91D Mg\|alloy satellite angle frame component was investigated by means of inston material test machine and metalloscope.The results showed that the prepared component with the strength of 292 MPa and the elongation of 4.8% was obtained at heating temperature of 560 ℃ for holding time of 20 min.For the billet,pre\|heating temperature of 400° for the die and for dwelling time of 40 seconds.The effect of thixoforming on the microstructure was realiged by separating liquid phase from solid phase while there was no effect on grain shape of solid phase.The billet flow way was characteriged by spheroidal solid phase clad with liquid phase during thixoforming process.The strength of the component can be increased by plus 10% through solid solution treatment for 6 h and natural ageing.关键词：Semi-solid;Thixoforming;AZ91D Magnesium Alloy;Mechanical Properties
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发布时间：2023-12-18 -
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- 摘要：The distribution of electromagnetic field in electromagnetic casting was calculated by the coupled circuit model.It was found that there was a linear relationship between the magnetic flux density and the input current.A proposed mehod to calculating height of liquid column was suggested and the relationship between current and height of liquid column was introduced in electromagnetic casting based on above results.The simulated results is well in agreement with the measured ones.关键词：Electromagnetic Casting;Model of Coupled Circuit;Electromagnetic Field;Height of Liquid Column
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发布时间：2023-12-18 - 摘要：Design and practice of measuring and control system for die casting machine based on Windows images interface were introduced.Pressure sensor,displacement sensor and deformation sensor were selected.The un\|loading delay was introduced into the hand system,meanwhile,the time delay was set.关键词：Diecasting Machine;Measuring and Control System;Windows
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发布时间：2023-12-18 - 摘要：The finite differential method is adopted to resolve the temperature fields of both roller sleeve and strip during twin roller casting rolling.The release of the solidification latent heat of molten aluminum is dealt with an enthalpy model.The distribution of temperature field of roller sleeve and strip have been obtained.The average interfacial heat transfer coeffiecient [8140 W/（m 2·℃）]between rolling strip and roller sleeve is obtained by FDM combined with opmization.关键词：Twin-roller Casting Rolling;Numerical Simulation;Temperature Field;FDM
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发布时间：2023-12-18 - 摘要：The analysis of vibration performance of die casting Mg alloy instead of Al alloy used for cooling impeller was conducted.The main modal variables,including intrinsic frequency and shape were obtained by modal experiment.The specific damping coefficient （SPC） of AZ91D and A380 were measured by amplitude deamplication.Compared to the aluminum alloy cooling impeller,the magnesium alloy cooling impeller was slightly changed in modal parameter but increased in SDC by more than ten times,which highly improved the vibration performance and reduce the operating noise for the impeller.关键词：Mg Alloy;Modal Analysis;Specific Damping Coefficient;Vibration Performance
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发布时间：2023-12-18 -
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- 摘要：Recently the well developed squeezing casting is becoming a effective technology for the production of die module.Practical die structure and processing parameters for forging die module in squeezing casting were shown.The combination structure was adopted for both punch die and container with the cooling water channel.The auto resetting bottom ejector suitable for general hydraulic presses without the bottom ejector is installed on the die.Service life of the die can meet reguirements for productive usage.There was no cavity for inner module.Results showed that the cast defects were eliminated with full fine grains for 4Cr5W2SiV,5CrMnMo,5CrNiMo,3Cr2W8V tool steel in sgueezing casting at pressure in excess of 150 MPa.The mechanical Properties of cast steel were well in agreement with forging steel.
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发布时间：2023-12-18 - 摘要：The origination of surface groove, that is the uneven oxidation of casting surface, was analyzed based on oxidation of the alloy at high temperature accroding to the structure, morphology and composition of the defects. It is found that the oxidation tendency can be controlled with uniformly oxidated casting surface关键词：Investment Casting;Silica Sol Mold Shell;Surface Groove;Steel Casting
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发布时间：2023-12-18 - 摘要：The relationship between XD 1 ceramic cores quality for directional hollow blade and chemical composition of Al 2O 3 filler for baking was discussed. It is one of the main factors that an excess of Na 2O would result in degradation of ceramic core quality.关键词：Ceramic Core;Hollow Blade;Na 2O
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发布时间：2023-12-18 - 摘要：Kaolinite refractory materials substituted for silica sand/powder can improve dimensional stability and strength of solica sol sodium solicate compound mold shell. Firstly, wax pattern tooth face was sprayed with a layer of slurry, and then stained with slurry, which can improve the clarity tooth face profile and avoid gas hole. The impeller core with special core materials can be substituted for with ceramic core sucessfully.关键词：Solica Sol Shell Making;Kaolinite;Tooth Parts in Investment Casting;Impeller
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发布时间：2023-12-18 -
- 摘要：The main technology and problems in Al manifold for V6 engine in LFC were introduced.Origination and elimination of slag hole in Al alloy casting in LFC were expounded.关键词：LFC;Engine;Al Manifold
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发布时间：2023-12-18 - 摘要：A 3-D CAD system for grey iron and ductile iron in lost foam casting was developed based on UG software with Standard C under NT operation system.The system can offer the whole course of EPC technological design with output of correlative 2 D drawing and card,technological parameters,riser system and gating system,castings’ arrangement in the mold flask as well as abundant general figure base and database.The system possessed friendly man machine interaction interface and mighty calculation ability.关键词：3D CAD;Expendable Pattern Casting;UG
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发布时间：2023-12-18 - 摘要：The effects of the alloying elements,such as Cu,Mg,Mn,Fe,in ZL108 alloy on tensile strength at high temperature were studied by orthogogal test.The quantitative empiric formular between the alloying elements and tensile strength of the alloy at 300 ℃ was established by multi element regression with four elements and their interaction.The effects of alloying elements on elevated strength at high teperature of the alloy were responsible for formed complicated intermetallic compound.Mg and Fe can improve greatly the tensile strength of the alloy at high temperature.The reaction of Cu and Mn with other elements revealed thermal strengtherning effects.关键词：Al-Si Alloy;Strength at High Temperature;Alloying Element
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发布时间：2023-12-18 - 摘要：The （Al 2O 3）/Al composites were prepared by in situ reaction method. The generated uniformly distributed Al 2O 3 particle possessed large dispersitity without accumulation or segregation. The analysis of microstructure of prepared composites showed that （Al 2O 3） P and matrix were well bonded and appeared no of new phase in interface. It is found that the tensile strength of the composites was increased by 25.6% while the elongation was only decreased by 9%. The addition of Al 2（SO 4） 3 can not only refine Al 2O 3 particles but also fovor refinement and dispersion of ceramic phase.关键词：In-situ;Al 2O 3 Particle;Composites
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发布时间：2023-12-18 - 摘要：The high Al,Zn base alloy conical gear with straight tooth in squeezing casting can ensure an accuracy of tooth face.The squeezed gear suitable for better operating condition with light load can decrease unit cost and working time so as to reduce production cost.关键词：Sgueezing Casting;High Al-Zn Base Alloy;Gear
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发布时间：2023-12-18 - 摘要：B loss in melt mainly occures in B addition followed by alloying process,next at melt holding during smelting and pouring.The B content can be rationally controled with enhancing deoxidation and coverage.B trends towards surface coagulation at melt holding during pouring. w （B） =0.013% can refine greatly as cast microstructure,with occurence of needle like and block like phase in high magification while no needle like phases occur in lower B content.It is founded that the block like phase consits of a rich in B coumpound with As and other inpurities by DEX.Melt strongly erodes silica sand lining.关键词：HSn70-1B;B;Melt;Structure
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发布时间：2023-12-18 - 摘要：The particular working condition of the coating of pouring channel in centrifugal casting was expounded.Attention is paid to bonding mechanism and influencing factors between coating and pouring channel.The ingredient of the coating and pertinent spraying technological parameters were given.关键词：Water Cooled Centrifugal Machine;Coating of Pouring Channel;Ductile Iron Pipe;Bonding Strength
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发布时间：2023-12-18 -
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