最新刊期
卷 33 ， 期 3 ， 2013
- 摘要：Through exerting a steady electric field on Al-9Si binary alloy in the mushy zone and liquid phase zone above liquidus,influence of electric field on the morphology and size of the primary α-Al in solidification microstructures of aluminum alloy was investigated.Temperature data during the cooling process of Al-9Si melt was measured and collected with temperature recording instrument XJY-160,and the solidification microstructure was analyzed by OM（optical microscope） and Image pro plus software.The results show that with the increase of current density,the size of primary α grains are decreased first rapidly and then slowly under a steady electric field,and critical current density is 330 mA·mm-2.Both the Pinch effect and thermoelectric magnetohydrodynamic（TEMHD） caused by steady electric field are responsible for restraining dendirtic growth of the primary α-Al grains in the Al-9Si alloy.关键词：Aluminum Alloy;Primary α-Al phase;Steady Electric Field;Solidification Microstructures
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发布时间：2023-12-18 - 摘要：A new technique was put forward to strengthening infiltrating effects through centrifugal forcing Zn alloy melt flow through ceramic foam assembly with high density and large thickness.The results show that the tensile strength and elongation of the zinc alloy whose melt is infiltrated by the method proposed are improved by 12.26%and by 30.37%,respectively,compared with those of the alloy without infiltration treatment,and the method is obviously superior to the flux refinery in refining effects.The structure of the alloy infiltrated was investigated by SEM（scanning electron microscope） and OM（optical microscope）.The results indicate that the inclusion with more than 15 μ m in size can be effectively removed from the alloy by strengthening infiltration,and the fracture mechanism of the alloy is characterized by quasi-cleavage mode with large region dimple from typical brittle cleavage mode.关键词：Ceramic Foam;Centrifugal Force;Zinc Alloy
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发布时间：2023-12-18 - 摘要：<正>近日,包头市大川机械科技有限公司以稀土、陶瓷为主要原料,采用先进高温聚合技术,成功研制出摩擦因数稳定、磨损率小、柔韧、低噪、制动平稳等优越性能的新型稀土复合材料矿用车刹车片,这也是国内首次研制出该类产品。包头市大川机械科技有限公司是内蒙古留学创业园的海外留学人员创办企业,由留学法国的两
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发布时间：2023-12-18 - 摘要：<正>现代交通惯用的内燃机,通常采用化石燃料与空气中的氧燃烧反应产生的化学能,转换成有用的机械动能和有害的温室气体排放。而目前相对流行和正在加速研发的绿色替代解决方案,主要为基于锂离子蓄电池电动汽车、氢燃料内燃机和加入部分可再生生物质混合燃料的发动机技术。欧盟第
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发布时间：2023-12-18 - 摘要：<正>近日,北京汽车股份有限公司-兰州理工大学战略合作框架协议签字仪式暨汽车轻量化联合研发中心揭牌仪式,在北京汽车产业研发基地举行。北汽集团总工程师、北汽股份副总裁高卫民,
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发布时间：2023-12-18 - 摘要：<正>从云南钛行业协会2013年高峰论坛上获悉,云南省将首次引入澳大利亚优质矿企——澳大利亚第四大矿产公司AIR,建设年产钛矿30万吨的生产基地。云南省钛矿资源丰富,保有储量1273万吨,居全国第二。1996年成立的云南钛行业协会,旗
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发布时间：2023-12-18 - 摘要：<正>近日,西安航空基地与陕西工业技术研究院等3家企业共同签订协议,"航空镁合金产业园"项目正式落户航空基地。该项目一期"高效节能镁合金板带示范线"建成后,可实现镁合金相关产品年产7万吨以上。镁合金是制造工业中可使用的最轻金属结构
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发布时间：2023-12-18 - 摘要：<正>黄金储备不足,似乎已经成为人民币国际化的重大短板。"应当择机增储,至少2000吨,力争3000吨的国家黄金储备,达到与德国、法国基本相当的水平,才能为人民币国际化提供强有力的支撑。"2月19日,紫金矿业集团股份有限公司副董事长、民生证券首席经济学家邱晓华,在接受
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发布时间：2023-12-18 - 摘要：<正>2013年1月25日,香港压铸及铸造业总会组织举办的"第十七次企业参观交流联谊会",首次走进广东伊之密精密机械股份有限公司,该活动被香港工业专业评审局列为"会员终身学习计划"认可课程活动。香港压铸及铸造业总会谢国夫会长、蔡子芳副会长等一行50余人受到了伊之密公司压铸机事业部李业军总经理众高层领导的热情接待。
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发布时间：2023-12-18 - 摘要：The micro-fracture morphology of the alloy under high strain rate tension and compression loading were observed by scanning electron microscopy（SEM） and optical microscopy（OM）.The tension and compression were conducted along extrusion direction and transverse direction,respectively.The results show that the compression fracture is characterized by brittle mode,while the high strain rate tension fracture is characterized by mixed mode of ductile and brittle.With increasing in the strain rate,the fracture tendecy of brittle to ductility is increased.Besides the fracture,the failure modes of extruded AM30 magnesium alloy under high strain rate belong to adiabatic shear band and crack propagation.关键词：Magnesium Alloy;High Strain Rate Tension;High Strain Rate Compression;Fracture Morphology
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发布时间：2023-12-18 - 摘要：Hot-corrosion behavior of Co-10Cr,Co-25Cr and Co-10Cr-5Al alloys with Na2SO4 film in the air at 900 ℃ was observed.The results indicate that the corrosion weight-increment of Co-10Cr alloy becomes the highest and then Co-10Cr-5Al alloy,Co-25Cr alloy.The corrosion products of Co-10Cr are composed of three layers,the outside layer of CoO,the middle layer of Cr2O3 and the inside layer with small amount of Cr2S3.The corrosion products of Co-10Cr-5Al consist of three layers,the outside layer of CoO,the middle layer of Cr2O3 and Al2O3,and the inside layer with a small amount of chromium sulfide and aluminum sulfide.Co-25Cr alloy is composed of CoO and Cr2O3 in the outside layer and single Cr2O3 in the inside layer with absence of distinct inside sulfide.关键词：Co-Based Alloy;Na2SO4 Salt Film;Hot-Corrosion
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发布时间：2023-12-18 - 摘要：The corrosion resistance of the graphite-like carbon coating on the cast GW93 magnesium alloy deposited by non-equilibrium magnetron sputtering was investigated through electrochemical methods as EIS and the Tafel polarization curves validated by agravity.Microstructure was observed by SEM and to analyze the influence on corrosion resistance.The results show that the composite coating is composed of chromium layer,transition layer and carbon layer.The growth modes of the coating are characterized by island structure.The graphite-like carbon coating can improve the corrosion resistance of the GW93 magnesium alloy as a result of improving the EIS to 5.0×1019 Ω and the self-corrosion potential to-0.940 V with background vacuum degree of 8.8×10-3 Pa.The background vacuum degree is a important factor influencing the corrosion resistance of graphite-like carbon coating,where corrosion resistance of the coating is improved increasingly with the increasing in background vacuum degree.关键词：GW93 Magnesium Alloy;Graphite-like Carbon Coating;Corrosion Resistance;Self-corrosion Potential
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发布时间：2023-12-18 - 摘要：Simulation of solidification process and the thermodynamic relation between temperature and equilibrium precipitated phases in H13 steel with Nb and high Mo contents have been investigated based on the Scheil module and Ploy-3 module in the Thermo-calc thermodynamic software.Meanwhile,the segregation behavior of alloying elements in the steel tested was also discussed.The result of element segregation was presented and equilibrium partition coefficient of alloy element was obtained by linear regressions depending on the Scheil-Gulliver equation and the Origin8.0 soft.The results show that the mass fractions of C,Nb and V is decreased sharply when solid fraction reaches 90% as a result of MC carbide precipitation.The equilibrium partition coefficients K0 of C,Si,Mn,Cr,Mo,V and Nb are less than 1,which is consistent with literature data.The high temperature homogenizing treatment process atn（1 2501 270） ℃×（46） hours and multi-passes forging has been suggested,which reduces segregation and improves the comprehensive properties of the steel tested.关键词：H13 Steel with High Molybdenum;Niobium Microalloying;Microsegregation;Equilibrium Partition Coefficient;Solidification Process
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发布时间：2023-12-18 - 摘要：The characteristics of the casting-forging hydraulic press with 6 000 kN and its die were described.The process of casting-forging and the microstructure as well as mechanical properties of A356 aluminum alloy prepared by the casting-forging technology were investigated.The results show that the casting-forging hydraulic press manufactured by self-designing has multi-functions such as side feeding,press casting and precision forging.The gas-entrappment in the parts can be avoided through the low speed casting.The soundness and the mechanical properties of the parts can be improved significantly through the forging with large area and large deformation.The tensile strength of A356 aluminum alloy parts with T6 heat treatment is 320335 MPa,increased by 17% compared with that of A356 aluminum alloy parts without forging.关键词：Integrated Forming Technology;Press Casting;Forging;Shrinkage Porosity
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发布时间：2023-12-18 -
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- 摘要：The hot deformation tests were conducted for Ti3Al-based alloy by THERMECMASTER-Z thermal simulator.The flow stress data was obtained at temperatures of 9501 350 ℃,strain rates of 0.00110 s-1 and maximum true strain of 1.2.According to the characteristic of empirical data and the theory of BP neural network,modeling of the high temperature constitutive relationship of Ti3Al-based alloy was built up.The results show that the constitutive relationship model of BP neural network exhibits a higher prediction accuracy,which can be used to FEM simulation of Ti3Al alloy during thermal deformation process and to guide the hot working process.关键词：Ti3Al-based Alloy;Constitutive Relationship;BP Neural Network
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发布时间：2023-12-18 - 摘要：The theory and thought of numerical simulation and the application of CAE technology were introduced,and a aluminum alloy volute casting and a aluminum alloy wheel were presented as practical low-pressure casting cases.The results show that the simulation results of low-pressure module in InteCAST CAE are consistent with the facts.Practical applications show that low-pressure casting CAE technology can effectively help designers judge the rationality of the casting technique,and it can also help assist in the improvement of casting technique.关键词：Low-pressure Casting;CAE;Numerical Simulation;Process Optimization
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发布时间：2023-12-18 - 摘要：Through orthogonal experiment integrated with the Huazhu CAE,the filling process of large steel gear parts was simulated under different processing conditions.With the help of comprehensive mark in fuzzy mathematics,three goals,such as the shrinkage rate,the number of shrinkage and the product yield of large steel gear parts,were evaluated individually and comprehensively,respectively,to determine the influencing importance and trends on goals including the standard cylindrical shape of the riser,height of standard cylindrical riser,parameters of standard waisted circular riser,the shape of standard waisted circular riser,the number of cylindrical riser.Through the weighted scoring method,the optimized design was presented,and simulated results were verified.关键词：Orthogonal Experiment;Simulation Analysis;Optimized Design
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发布时间：2023-12-18 - 摘要：An experimental equipment with inclined plate cooling and shearing has been developed to prepare semi-solid ZL104 alloy slurry.The effects of inclined plate angle on microstructure refinement and spheroidization in semi-solid ZL104 alloy were investigated.The results show that the inclined plate angle has remarkable effect on physical metallurgy and shear action of ZL104 alloy.Fine spherical grain in the semi-solid ZL104 alloy slurry can be obtained in range of 30 ° 45 °,and the major grain equivalent diameters are less than 43 μm and more than 40% of the grain shape factor is in 0.75 above at 45 °,exhibiting better grain fine degree and roundness.关键词：ZL104 Alloy;Semi-solid Forming;Inclined Plate Angle;Microstructure;Spheroidization
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发布时间：2023-12-18 - 摘要：Near-liquidus techniques was adopted to prepare C-grade steel semi-solid melt,and rheological filling behavior of the semi-solid melt in metal mold under external pressure was investigated.The results indicate that,with the increase of filling pressure and mold preheat temperature,rheological filling behavior of low-alloy steel semi-solid melt is improved increasingly.In addition,the effects of mold preheat temperature is higher than filling pressure on filling behavior.The rheological filling capacity of low-alloy steel semi-solid melt is improved by increasing the pouring volume.Optimization of pressure chamber volume and runner length during design of mold is the key important for desirable filling of semi-solid melt.关键词：Low-Alloy Steel;Semi-Solid Melt;Filling Capacity;Processing Parameters
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发布时间：2023-12-18 - 摘要：The refining effects of temperature-induced irreversible liquid-liquid structure transition,low melt temperature and high-low temperature melt mixing ratio on primary silicon in the Al-18Si alloy were investigated by melt mixing treatment.The effects of low-melt temperature and mixing ratio of high-low temperature melt on refinement of primary Si have been summarized,and the action mechanism of high-temperature melt state and semi-solid-state low-temperature melt has been also analyzed.The results show that the primary silicon in the alloy slurry is remarkably refined by melt mixing treatment mixed at a proper ratio when the high-temperature melt is heated to a temperature which has undergone melt structure transition and the low-temperature melt is held at a proper temperature in range of semi-solid zone,where the average size of primary silicon is refined to less than 12 μm.关键词：Melt Mixing Treatment;Melt State;Hypereutectic Al-Si Alloy;Primary Silicon Refinement
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发布时间：2023-12-18 - 摘要：The semi-solid 7075 aluminum alloy slurry was prepared by the inverted-cone channel technology.The effects of forming temperature,injecting pressure and injecting chamber temperature on the filling ability of semi-solid 7075 alloy slurry were investigated.It is demonstrated that a higher forming temperature is favorable of the good filling ability.Injecting pressure and injecting chamber temperature have an effect on the filling ability too.The higher the injecting pressure is,the better the filling ability is.Besides,the results also show that the microstructure distribution of semi-solid 7075 alloy is homogeneous and compact,which is helpful to obtaining high quality castings.关键词：Inverted Cone-Shaped Channel;7075 Alloy;Rheo-diecasting;Semi-solid;Filling Behavior
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发布时间：2023-12-18 - 摘要：aiming at problems existed in the traditional die casting super-thickness product,such as high porosity,low strength,the ultra-low-speed die casting engine support bracket was conducted,and effects of different injection speed,the thickness of ingate,pouring temperature of liquid metal,the mould structure and the control methods of the mould temperature on the quality of die casting support bracket were discussed.The results show that the support bracket exhibits acceptable quality with low injection speed of 0.25 m/s and high injection speed of 0.5 m/s,thickness of ingate of 5.2 mm as well as pouring temperature of 680690 ℃.Through modifying die casting die structure and adopting the sequential solidification mould temperature,the support bracket ca be treated by T6 heat treatment,improving greatly the performance of the die castings.关键词：Aluminum Alloy;Ultra-Low-Speed Die Casting;Automobile Engine Cap
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发布时间：2023-12-18 - 摘要：The effects of shot parameters and artificial aging treatment on the microstructure and mechanical properties of the die-casting Al-5Mg-2Si-Mn alloy were investigated.The results show that the die casting samples exhibits good surface with sound microstructure and absence of shrinkage and gas porosity under the condition of shot pressure 100 MPa,high-speed injection velocity and the shrift position of 220 mm.The tensile strength,yield strength and elongation can reach up to 351.1 MPa,200.7 MPa and 13.77% respectively.After artificial ageing treatment at 250 ℃ for 3 hours and then cooled in air,tensile strength,yield strength and elongation of the samples can reach 380.5 MPa,246.9 MPa and 11.48% respectively.关键词：Die Casting;Al-5Mg-2Si-Mn Alloy;Microstructure;Mechanical Property
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发布时间：2023-12-18 - 摘要：<正>俄罗斯托姆斯克工业大学的研究人员用碳离子的短脉冲波作用于硅,在硅表面合成纳米金刚石粒子和碳粒子,在世界上首次研究成功在其他物质表层内部合成纳米金刚石粒子的方法。这种方法的研究成功能够改变金属制品和半导体的某些性质,能够让某些材料变得更加坚固,提高其耐磨性
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发布时间：2023-12-18 - 摘要：Corundum-spinel crucible was developed.Practical use results show that service life of corundum-spinel crucible can reach 150 cycles with smelting 304 stainless steel in 150 kg main frequency furnace.The crucible can not only be free the man-made brasque but also improve significantly the purity of the liquid steel.Meanwhile,the use and problems of the corundum-spinel crucible were described,and the countermeasures were presented.关键词：Crucible;Corundum-Spinel;Main Frequency Furnace;Brasque;Investment Casting
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发布时间：2023-12-18 - 摘要：Origination of iron sweat in the inner cavity of high accuracy impeller castings was presented by endoscope.Gas porosity defect in sub-surface of urea core can be eliminated increasingly by the improvement of urea melting unit to control liquid urea temperature,thereby iron sweat in the inner cavity of high accuracy impeller castings is relieved.A modification on structural design for impeller molding with a separate adherence and an aluminum loose piece core for blades in impeller internal cavity can improve significantly surface quality to meet customers’ requirements on surface roughness.关键词：Impeller;Iron Sweat;Urea Core;Sub-surface Gas Porosity;Surface Roughness
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发布时间：2023-12-18 - 摘要：Talcum powder and diatomite as refractory aggregate and sodium bentonite and CMC as composite suspension agent as well as sol silicate and PAM as composite binder were selected,and the proportion of talcum powder and diatomite was determined based on coating strength,permeability,brushability,suspension property,density,adhesive quantity and dripping properties.Proportion of sodium bentonite,CMC sol silicate and PAM was presented through testing strength,suspension property and viscosity of the coating.Based on the optimized proportion,the coating was developed.Through pouring experiment,the coating exhibits feasible.关键词：Lost Foam Casting（LFC）;Aluminum Alloy;Coating
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发布时间：2023-12-18 -
Development of Subnano Particles Modificational Function Coating and its Application in Steel Sleeve
摘要：Through compound modification treatment for coating with help of adding sub-nano RE alloy and alkali metal salt during centrifugal casting thick-walled casting steel sleeve,the solidification sequence of the steel sleeve could be controlled to reduce the undercooled rate of outer solidification of steel sleeve and refine grain size as well as controlling the directional growth of carbide in the steel sleeve,resolving the problems of thermal transferring during solidification process and eliminating the presence of crack.Based on the Lewis acid-base theory from the chemical point of view,the modification mechanism of the cerium-based rare earth alloy on steel was analyzed.The sulfur content in the steel sleeve was controlled.Subnano particles can greatly increase the number of heterogeneous nucleation substrate,and further reduce the solidification undercooling of outer steel sleeve as well as improving the coating suspension.After the steel sleeve solidified,the collapsed coating can be reclaimed,realizing green casting.关键词：Centrifugal Steel Sleeve;Rare Earth Alloy;Modification;The Lewis Acid-Base Theory- 2
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发布时间：2023-12-18 - 摘要：A new continuous core-filling casting machine for copper cladding aluminum composite bars was designed and produced.The machine installed the upper and bottom graphite crucibles in the vertical direction for heating inner core of aluminum and the outer layer of copper.During continuous casting,copper tube was formed in the crystallizer continuously firstly,then liquid aluminum was injected into the copper tube through mandrel.Finally,the metallurgical bonded layer was formed by inter-diffusion between copper and aluminum.The copper cladding aluminum composite bars with the core thickness of 10 mm and the sheath thickness of 2 mm and the width of 60 mm were fabricated successfully by the machine.关键词：Copper Cladding Aluminum;Core-filling Continuous Casting;Composite Bars
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发布时间：2023-12-18 - 摘要：The open cell Nickle-adulterated alumina foam ceramics were prepared by impregnating a polymeric sponge with aqueous ceramic slurry.The Nickle-adulterated alumina foam ceramics with a very uniform macrostructure and few flaws were produced by recoating process.A nickelousnitrate liquid-phase coating and deoxidized by hydrogen method was used to deposit Ni on the surface of Ni-adulterated alumina foams.Coating morphology and microstructure of the foam ceramics were observed by SEM（scanning electron microscope） and EDS（energy dispersed spectrometer）.The results indicate that Ni particles are distributed uniformly in the foam skeleton and pores in the sintered body exhibit interconnected.Furthermore,Ni is successfully coated on alumina foams surface after coating process.关键词：Foam Ceramics;Nickle-adulterated;Nickle-coated;Microstructure
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发布时间：2023-12-18 - 摘要：Al2O3/Cu composites were prepared by internal oxidation,by cold pressed sintering and by SPS,respectively.The properties of the composites prepared by the three methods were tested,and the microstructure was observed by scanning electron microscope（SEM）.The experimental results show that the Al2O3 particles of the composite prepared by internal oxidation are more evenly distributed in the copper matrix,and the hardness（HBS） can reach up to 115,exhibiting the desirable comprehensive properties.The comprehensive properties of the composites prepared by cold sintering method are inferior to those of internal oxidation composite.The relative density and the electric conductivity of the composite prepared by SPS reach 99.18% and 55.68 MS/m,however,the hardness is lower than the other two.关键词：Al2O3/Cu Composite;Preparation;Density;Hardness;Electric Conductivity
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发布时间：2023-12-18 - 摘要：Effects of vacuum degree on the oxidative combustion and volatilization level of liquid AZ91D magnesium alloy were investigated.The AZ91D alloy samples in different vacuum conditions were analyzed by EDS,and surface morphology of the protective film was observed.The results show that vacuum degree of 50 kPa is a critical value for counter-pressure casting AZ91D magnesium alloy.When the vacuum is below 50 kPa,oxidation combustion phenomenon occurs on surface of liquid AZ91D magnesium alloy,and with the decrease of the vacuum degree,magnesium content is declined sharply,resulting in the more serious volatilization of the liquid magnesium.When vacuum degree is more than 50 kPa,magnesium content in the sample is near to standard content,and surface morphology exhibits more and more continuous and sound,inhibiting greatly magnesium combustion phenomena.There exists holes and crack in surface morphology with vacuum degree below 50 kPa.A mathematical model between magenisum contents and vacuum degree was presented,which could provide a guide to counter-pressure AZ91D magnesium alloy.Optimized vacuum degree for counter-pressure casting AZ91D magnesium alloy is 50 kPa.关键词：Vacuum Degree;Oxidative Combustion;Surface Morphology;Volatilization Level;Mathematical Model
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发布时间：2023-12-18 - 摘要：Effects of ageing treatment on mechanical properties and electric conductivity of 6063 alloy were investigated.The results show that with increasing in aging time within 12 hours,the strength and electric conductivity of the 6063 alloy with aged at 185 ℃ are improved,and elongation is decreased.With aged at 205 ℃ for 4 hours,the tensile strength,yield strength and electric conductivity reach the maximum value of 215.4 MPa,190.5 MPa and 32.37 MS/m,respectively,and the elongation is 10.3%.关键词：6063 Alloy;Ageing Treatment;Mechanical Properties;Electric Conductivity
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发布时间：2023-12-18 - 摘要：The compound refining treatment of self-developed Al-TiC grain refiner and Al-5Ti-B master alloy on the Al-7Si-Mg alloy was performed to investigate the effects of composite refining process on the grain size and mechanical properties of Al-7Si-Mg.The results show that the grain size of Al-7Si-Mg alloy refined by composite refining process is 66.5% of that refined by 2% Al-5Ti-B.Compared with those of Al-7Si-Mg alloy refined by 2% Al-5Ti-B,the tensile strength of the Al-7Si-Mg alloy refined by composite refining process is increased by 13.88% and 4.96%,and the elongation is increased by 52.3% and 89.3%,respectively,before and after T6 treatment.关键词：Al-TiC;Al-7Si-Mg Alloy;Composite Refining;Grain Size;Mechanical Properties
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发布时间：2023-12-18 - 摘要：Fracture morphology and microstructure of ZL102 alloy polishing machine buckle was observed and analyzed by scanning electron microscopy（SEM） and metallurgical microscope.The results show that microstructure of the ring sample is composed of α-Al phase,coarse acicular eutectic Si phase and blocky primary Si phase as well as a small amount of skeleton-like shape the T1（Al7Fe2Si2） and the fine needle-T2（Al5FeSi） iron-rich phase.Different cleavage facets with different orientation can be observed in alloy fracture surface,and the crack occurs as a result of transgranular cleavage fracture,which is characterized by ray florets and cleavage steps.The excessive brittle iron-rich phase,casting porosity and inclusions can weaken the binding force of the grain boundary,leading to brittle fracture of alloy.关键词：Casting Al-Si Alloy;Fracture;Microstructure;ZL102 Alloy
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发布时间：2023-12-18 - 摘要：The AlCrMnMoNiZr（B0.1） high entropy alloys were prepared by powder metallurgy process.Microstructure and hardness of the as-cast and annealed alloys were characterized by X-ray diffraction,scanning electron microscopy and digital display Vickers hardness tester.The results show that the as-cast alloys are composed of a mixed structure of BCC solid solution phase（in-rich Cr,Mo） and intermetallic compound.After annealed at 7001 000 ℃,absence of the phase and structure change in the alloys can be observed.The hardness of alloys at as-cast and annealed remains above 525 HV,showing a excellent high temperature stability.In addition,the hardness of the as-cast alloy is enhanced from 528 HV to 741 HV because of the solution strengthening of minor B element.关键词：Powder Metallurgy Process;High Entropy Alloy;Microstructure;Age-hardening;High Temperature Stability
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发布时间：2023-12-18 - 摘要：<正>瑞兽葡萄镜唐代（公元618年-907年）直径14.5cm,质量991g高锡青铜铜镜是观容鉴貌的用品。古人最早以止水鉴容,之后出现了铜镜,与古人朝夕相伴二千多年,直到出现玻璃镜之后方才离开人们的生活。作为一种实用工艺品,各个时代创造出不同风格的铜镜,特别是战国、汉、唐的铜镜,不仅人文艺术内涵丰厚,铸造精湛,极少铸造缺陷,表面装饰亦华丽多采,构筑了中国古代铜镜艺术的三大颠峰时期。由于古铜镜蕴涵大量信息,所以同内外研究中国古代
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发布时间：2023-12-18
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