最新刊期
卷 34 ， 期 3 ， 2014
- 摘要：Using first-principles pseudo-potential plane wave method,the formation enthalpy,cohesive energy,density of states and electric density of difference were calculated and analyzed for NiTi（B）and NiTi（Nb,B）phase after boron elements adulterating process.The results show that in NiTi basic crystal,boron atom has much more formation ability in 4Ti2Ni octahedron structure than that in 4Ni2Ti. However,in NiTi（Nb）solid solution crystal,the nearest neighbor site of B-Nb is more stable than the next nearest neighbor site,and the formation ability of the former impurity site is stronger than the next one.The simulation of density of states and electronic density difference shows boron preferring to bonding with Ti atoms and Nb atom,while the bond strength of B-Ni is weak.Such bonding process results in the action of Ti atoms decreasing and the ratio of Ni/Ti increasing,deteriorating the properties of NiTiNb alloy by boron impurity.关键词：NiTiNb Shape Memory Alloy;Boron Impurity;Structural Stability;Microcosmic Mechanism
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发布时间：2023-12-18 - 摘要：AZ31 magnesium alloy sheets were fabricated by severe strain rolling,and effects of rolling temperature on microstructure,texture and mechanical properties of the sheets prepared were investigated.The results show that large strain rolling can be used successfully to fabricate AZ31 magnesium alloy sheets in the temperature range of 250400 ℃,while crack occurs with rolled at 200 ℃.The dynamic recrystallization（DRX）grain size and maximum pole density of the sheets rolled in range of 250 400℃ are increased while the mechanical properties are decrease with the rolling temperature increase. The sheet rolled at 250 ℃ exhibits excellent mechanical properties,and the tensile strength,yield strength and elongation of the sheets reach 327.5MPa,213.2MPa and 29.8%,respectively.关键词：AZ31 Magnesium Alloy;Severe Strain Rolling;Rolling Temperature;Microstructure;Tex-ture;Mechanical Properties
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发布时间：2023-12-18 - 摘要：Based on the principle of differential pressure casting,the vacuum assisted differential-pressure infiltration method was newly developed to fabricate continuous carbon fiber reinforced aluminum matrix composites（Cf /Al）.Microstructure,fibre distribution,interface phase constituent and fracture morphology of the Cf /Al composites were investigated by scanning electron microscope（SEM）,transmission electron microscope（TEM）and X-ray diffraction（XRD）.Bending strength of the composites prepared was tested by three-point bending experiment.The results show that microstructure of the composites exhibit dense,and the fibers are distributed homogeneously with desirable bonding with the aluminum alloy.The fine Al4 C3 and Mg2 Si phase with small aspect ratios can be found which is distributed discontinuously at the C/Al interface.The bending strength of the composites reaches 1 078 MPa at room temperature.The partial fiber extraction and interface debonding on the fracture surface indicate obvious characteristic of ductile fracture in the composites,which can be attributed to the moderate interface strength of the composites.关键词：Cf /Al Composites;Vacuum Assisted Differential-Pressure Infiltration;Interface Structure;Mechanical Properties
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发布时间：2023-12-18 - 摘要：Effects of Si addition on the microstructure of Cu-7.5Ni-5Sn alloy were investigated by metallographic test,energy spectrum,XRD（X-ray diffraction）and SEM（scanning electron microscope）analysis.The results show that the as-cast microstructure change of Cu-7.5Ni-5Sn alloy is absent regardless of adding Si,which is composed ofαdendrites structure,α+γand Sn-richγphases.The Si can refine the microstructure and grain size in Cu-7.5Ni-5Sn alloy.The Si can react with the Ni atoms and form Ni31 Si12 phase,Ni3 Si phase and Ni74 Si26 phase,and Ni3 Si phases can refine the dendritic structure.In addition,Si can delay the homogenization process of Cu-7.5Ni-5Sn alloy.关键词：Cu-7.5Ni-5Sn Alloy;Si;As-cast Microstructure;Homogenization
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发布时间：2023-12-18 - 摘要：In order to improve the quality of metal mold coating for magnesium alloy,magnesia powder as aggregate for metal coatings was investigated,and effects of hexametaphosphate addition as binding agent on performance of the coating were analyzed.The experimental results reveal that the appropriate sodium hexametaphosphate addition can improve the strength,the viscosity and the dripping behavior of the coating,meanwhile,the coatings exhibit a certain yield value and thixotropic behavior.Metal coating for the magnesium alloy with magnesia powder as aggregate and 6% sodium hexametaphosphate addition presents desirable ability.关键词：Hexametaphosphate;Coating Performance;Metal Mold Casting
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发布时间：2023-12-18 - 摘要：Microstructures of a cast Ti-48Al-2Cr-2Nb alloy without melt treatment and with melt cycle treatment for 10,15and 20 cycles in solid-liquid region（1 4801 510℃）were investigated by OM coptical microscope and SEM（scanning electron microscope）.The results show that the melt treatment has a significant role in the refinement of grain sizes in the alloys.The microstructure of the alloy is characterized by coarse columnar morphology without melt treatment,while it is characterized by small fine equiaxed grain from coarse lamellar cluster with the melt cycle treatment for 10,15and 20 cycles,and it is more uniformly distributed in the microstructure.At the faster heating stages in the melt cycle treatment process,the remelting of grain occurs,resulting in the separation of broken dendrite with the matrix to act as nuclei in subsequently solidification.Meanwhile,under the action of electromagnetic force, the solute field and temperature field are uniformly distributed to inhibit the occurrence of composition undercooling,which is responsible for the refinement of grain size.关键词：Ti-48Al-2Cr-2Nb Alloy;Melt Cycle Treatment;Remelting of Dendrite;Electromagnetic Stir-ring;Grain Refinement
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发布时间：2023-12-18 - 摘要：The flow field of aluminum melt spinning purification was comparatively visualized by water simulation at variable stirring way,rotational speeds and argon gas flux.The results indicate that compared with the center stirring,eccentric stirring can effectively refine the bubble size,improve the distribution of the bubbles and inhibit the melt surface vortex.关键词：Spinning Purification;Simulation;Eccentric
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发布时间：2023-12-18 - 摘要：Effects of aging temperature and time on mechanical properties of 0Cr17Ni7Al stainless steel were investigated.The mechanical properties and fracture surfaces of the 0Cr17Ni7Al stainless steel were analyzed by the electronic universal testing machine and scanning electron microscopy（SEM）.The results show the ultimately fracture strength and plastic deformation of 0Cr17Ni7Al stainless steel are in the range of 19772030 MPa and 24%,respectively,with aging treatment at 410430 ℃,while effects of the aging time on tensile strength of 0Cr17Ni7Al stainless steel can be ignored.However,the plastic deformation is only 11% after aging treatment at high temperature.A large number of dimples and continuous vein morphologies are observed in 0Cr17Ni7Al stainless steel with aging treatment at 410 430℃,providing apowerful support for the plastic deformation.关键词：0Cr17Ni7Al Stainless Steel;Aging Treatment;Mechanical Properties
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发布时间：2023-12-18 - 摘要：Aluminum alloy pump body was produced by die casting,and filling and solidification process of pump body were simulated and analyzed by the ProCAST software.Based on the number of shrinkage porosity（holes）,the quality of the pump body was visualized.The practical product reveals that pouring temperature of the aluminum alloy melt exhibits a key role in quality of die casting pump body.The optimized processing parameters are presented as follows:injection speed of 5 m/s,mold preheating temperature of 200℃ and pouring temperature of 640℃.关键词：Aluminum Alloy;Numerical Simulation;Filling and Solidification;Pump Body
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发布时间：2023-12-18 - 摘要：To eliminate shrinkage porosity occurred in the hot spot in low pressure casting large size aluminum alloy wheel,the ProCAST software was adopted to understand the temperature field distribution during filling and solidification process.The mould and casting parameters were optimized according to the simulation.The cooling rate was improved by adding water-cooling ring in the mould,and the shrinkage porosity in hot spot was reduced effectively.The results show that the optimized process not only improves the performance of casting but also shortens the production time,greatly improving the production efficiency.关键词：Low Pressure Casting;Large Size Aluminum Alloy Wheel;Temperature Field
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发布时间：2023-12-18 - 摘要：Effects of liquid-solid mixing and mixing temperature of Al-25Si alloy on the microstructure and properties as well as the relationship between microstructure with thermal expansion coefficient and wear resistance of Al-18Si alloy which was prepared by CDS（controlled diffusion solidification）were investigated.The results show that during the CDS,the desirable microstructure with uniformly distributed round primary Si phase can be observed with mixed solid pure-Al at 630℃ with liquid Al-25Si at 850 ℃alloy,and wear resistance of the alloy exhibits desirable.The lower linear expansion coefficient（15. 51×10-6℃-1 from 30℃to 300℃）of the Al-18Si alloy can be achieved by the mixing of pure-Al at 630 ℃and liquid Al-25Si at 900℃.The wear resistance of Al-18 alloy Si is mainly dependent on the size, morphology and distribution of primary silicon.关键词：Hypereutectic Al-Si Alloy;Controlled Diffusion Solidification（CDS）;Linear Expansion Coeffi-cient;Wear Resistance
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发布时间：2023-12-18 - 摘要：Die casting mould structure of bracket was introduced,and principle and structure characteristics of the mould were described.The 3-plate mould has one cavity-one mould with three plate type and two parting lines,which uses point gate.The bracket pulls difficult due to its complex shape and many holes as well as thin wall,so the structure with ejector plate and ejector sleeve twin-ejection connected by hinges was adopted.The mould enhibits compact with works reliably and operates fully automatically.关键词：Twi-Ejection;Bracket;Hinges Connection;Point Gate;Die Casting Mould
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发布时间：2023-12-18 - 摘要：Through observing hard spots in aluminum die casting and analyzing production condition,the metallographic characteristics and types of hard spots have been identified,and origination of the hard spots was described.Aiming at different types of hard spots,a series of countermeasures from the aspects of process design improvement to strengthen production management were adopted,such as strengthening raw materials management,improving melting process design,selecting proper aluminum alloy furnace according to the product quality requirement,using ceramic filter and rotary spraying refinery as well as adopting graphite crucible instead of cast-iron crucible in holding furnace,adjusting melting and refining process,strengthening worksite regulation.关键词：Aluminum Alloy Die Castings;Hard Spots;Metallic Inclusion;Nonmetallic Inclusion
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发布时间：2023-12-18 - 摘要：Interfacial heat transfer coefficient（IHTC）during squeeze casting was calculated by measuring temperature near casting/mold interface based on non-linear estimation method combining with inverse calculation method,and effects of applied pressure on interfacial heat transfer were investigated.The results show that the peak values of IHTC are greatly increased with increasing in applied pressures,and the relationship between the peak values of IHTC and pressures is presented.By using the IHTC results as boundary condition,central temperatures of squeezing castings were calculated.The measured central temperatures of castings were obtained,which validated the accuracy of the IHTC results.关键词：Squeeze Casting;IHTC;Inverse Method;A356 Alloy
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发布时间：2023-12-18 - 摘要：Based on slow shot theory,the preset velocity was set,and the simulation mode of fuzzy control of slow shot was established based on the AMESim and MATLAB/Simulink platform.The closedloop control for the injection velocity was realized by the fuzzy control.The results reveal that the actual velocity is well in agreement with the preset velocity with fast responsiveness and absence of overshoot, so it can guide the control of slow shot speed in practice.关键词：Slow Shot;Critical Speed;Closed-Loop Control;Fuzzy Control
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发布时间：2023-12-18 - 摘要：Influences of vibration frequency on the microstructures and properties of semi-solid alloy ZL104 which was prepared and rheo-die casting by a self-designed inclined rheological experimental facility with adjustable vibration frequency were investigated.The results indicate that the microstructure of specimen formed is fine and round.With increasing in the vibration frequency,grain size in the microstructure is further decreased.Vibration frequency exhibits the key role in the tensile strength and elongation.With the increase of vibration frequency,the tensile strength,elongation,hardness and impact toughness of the specimen formed are increased.When the vibration frequency is 40Hz,the tensile strength,elongation,hardness and impact toughness reach 291MPa,7%,80.8HBS and 0.95kJ/m2 respectively.关键词：Vibration Frequency;Rheo-die Casting;ZL104Alloy;Microstructure;Properties
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发布时间：2023-12-18 - 摘要：Batches of cracking defects occur in large-scale steel investment castings with relative centralized location and a ratio of 30%to 50%.The stress field in the initial process was simulated by ProCAST software,and cracking defects were analyzed based on the simulation results.And then some improved processes were put forward and tested.Finally,desirable processing parameters were determined.Practical production reveals that the crack defect in the castings is decreased to 5%.关键词：Large-Scale Steel Investment Castings;Crack;ProCAST;Stress;Simulation Analysis
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发布时间：2023-12-18 - 摘要：Through experiment in wax pattern making,shell making,combination design of gating system,melting and pouring process,a series of new process were approached to eliminate the cold shut, misrun,shrinkage porosities and crack in gas turbine exhaust valve shell.The feasible process and parameters were determined,and the shell meeting the requirement was produced successfully.关键词：Shell;Misrun;Shrinkage Porosity;Crack
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发布时间：2023-12-18 - 摘要：The processing characteristics and basic production processes as well as applications in the aeronautical industry both at home and abroad of the investment casting technology were summarized. According to the melting and forming characteristics of different alloys,the investment casting technology for aluminium alloy,magnesium alloy,titanium alloy and super alloy used in aviation weapons equipments and manufacturing process of typical components were described.New special casting methods, extraordinary core technology,computer assisted design and numerical simulations,special forming equipment and technology as well as other key techniques were reviewed.The future research focus and development direction of investment casting technology applied in the aviation industry were predicted.关键词：Investment Casting;Aviation Industry;Aluminum Alloy;Magnesium Alloy;Titanium Alloy
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发布时间：2023-12-18 - 摘要：The austenite-bainite ductile iron for high speed grinding CBN wheels matrix was prepared by alloying treatment and controlling cooling velocity according to the demand for its size and properties in the lost foam casting（LFC）process.Experimental results reveal that for the samples with 20mm in thickness,by adding appropriate amounts of Cr,Ni,Mo,Cu and controlling the open-mold time of the casting,as well as keeping the castings using aluminum silicate fiber cotton in the austenite-bainite transformation temperature range,austenite-bainite ductile iron with the maximum hardness of 55 HRC and maximum tensile strength of 1000MPa can be obtained.关键词：Alloying;Lost Foam Casting;Cooling Velocity;Austenite-bainite Ductile Iron Matrix
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发布时间：2023-12-18 - 摘要：Based on experimental data,the rate of vaporization is constant when the parameter of lost foam casting is determined.Taking Al-alloy lost casting with EPS foam for example,in the condition of ρ模=3kg/m3,the rate of foam vaporization is equal to the traditional cavity casting.关键词：Lost Foam Casting;Rate of Foam Vaporization;Cavity Casting
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发布时间：2023-12-18 - 摘要：Carbon fiber reinforced magnesium alloy laminated plates are made of magnesium alloy and carbon fiber instead of glass fiber reinforced aluminum alloy laminated plates of aluminum alloy and glass fiber commonly used in modern aviation and aerospace engineering.Effects of loading velocity on fracture toughness of the composite layer of carbon fibre reinforced magnesium alloy laminated plates were investigated with the help of single cantilever.The results reveal that interlaminar crack is characterized by steady propagation mode in low load rate,while with the increase of speed,the instability of the crack propagation is increased.At low veloaty（1mm/min to 1 000mm/min）,load rate exhibits a slight effect on interlaminar fracture toughness.The interlaminar fracture toughness of composite laminated plates at high loading is higher than that at lower rate.关键词：Carbon Fiber;Magnesium Alloy;Laminated Plates;Loading Rate;Fracture Toughness
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发布时间：2023-12-18 - 摘要：Carbon nanotube reinforced ZM5 magnesium matrix composites were prepared by die casting. Effects of carbon nanotubes content on die characteritics and mechanical properties of the composites prepared were analyzed.In addition,effects on grain size and distribution in the matrix alloy were observed by OM（optical microscope）,and distribution of carbon nanotubes in the matrix alloy was observed by SEM（scanning electron microscope）.The results reveal that trace nano-tubes content can be ignored on effects of forming ability of the alloy.With 1.3% carbon nano-tubes,tensile strength of the ZM5 composites can reach 190MPa,and with 1.1% carbon nano-tubes,elongation of the composites is 6.25%,and with 1.5% carbon nano-tubes,the hardness of the composites prepared reach up to Hv95.2.关键词：ZM5Mg Alloy;Carbon Nanotube;Composites;Die Casting
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发布时间：2023-12-18 - 摘要：In situ Al2O3 particle reinforced Al matrix composites were synthesized by direct melt reaction assisted with indirect ultrasonic treatment in Al and CuO system.The results show that ultrasonic treatment can promote in situ reaction.With ultrasonic treatment,Al2O3 particles size is about 12μm in diameter with dispersedly uniform distribution both in the grains and the grain boundaries.Furthermore, the quantity of Al2 O3 particles with ultrasonic treatment is more than that without ultrasonic treatment. The optimal temperature of indirect ultrasonic treatment is about 665675 ℃.It is beneficial for the dispersed distribution and generation of Al2 O3 particles with holding at 875℃for 30min after ultrasonic treatment.The acoustic streaming effect and acoustic cavitation effect during ultrasonic treatment can improve wettability between Al melt and CuO powder and can disperse the agglomerated CuO powder. The mechanism of the promotion is the optimization of kinetic and thermodynamic environment in the reaction.关键词：Aluminum Matrix Composites;Ultrasonic;In Situ;Al2O3
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发布时间：2023-12-18 - 摘要：YBCO reinforced Cu matrix composites were prepared by hot-pressed sintering（HPS）,and effects of the different YBCO content on the structure and properties of copper-matrix composites,such as electric conductivity,density,hardness,were approached.The results indicate that with a lower YBCO content,YBCO particle is distributed uniformly in the matrix,while with high YBCO content,the agglomerates occurs.With the increase of the YBCO content,the electric conductivity and density are decreased,and the hardness is firstly increased and then decreased.With 3% YBCO content,the maximum hardness value can be observed.关键词：YBCO;Composite Materials;Electric Conductivity;Property
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发布时间：2023-12-18 - 摘要：The control of thermal baffle has an important role in the temperature gradient and the homogeneous temperature field in the process of single crystal superalloy solidification as a result of affecting the solidification microstructures of the single crystal superalloy,so it is necessary to analyze the thermal baffle.Influences of different thermal baffle thickness on the solidification microstructures of the second generation single crystal superalloy DD6 were investigated.The results reveal that with increasing in the thickness of thermal baffle,the temperature gradient is decreased in the process of single crystal superalloy solidification,while the angle between the single crystal growth orientation and the[001] orientation is narrowed.In addition,as the thermal baffle thickness increases,the primary dendrite arm spacing is increased,and the size and the volume fraction ofγ-γ′eutectic are increased too.Meanwhile, the size ofγ′phase in the primary dendrite and in the interdendrite is increased slightly accompanying with the increase of segregation ratio of main elements.关键词：Thermal Baffle;Single Crystal Superalloy of DD6;Solidification Microstructure;Temperature Gradient;Single Crystal Growth Orientation
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发布时间：2023-12-18 - 摘要：The second phase particles and inclusions in 3104 aluminum alloy ingot casting and fractures of defects on the ring-pull can were investigated by scanning electron microscope（SEM）,energy dispersive spectrometry（EDS）and X-ray diffraction（XRD）.The forming reason of defects were analyzed systemically by observing the second phase particles in original ingot casting.The results show that there exists a lot of（FeMn）Al6 phases,（Al,Fe,Mn,Si）compounds and coarse oxide-based inclusions.Fractures of the can mainly be attributed to those coarse particles and inclusions,which results from the process of melting or casting.Countermeasures of eliminating or reducing coarse compound and inclusions were put forward finally.关键词：3104 Aluminum Alloy;Secondary Phase;Oxide Inclusions
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发布时间：2023-12-18 - 摘要：Surface segregation layer thickness of 4032 alloy was examined by EDX spectroscopy,photoelectric direct reading spectrometer and metallographic method.The results show that photoelectric direct reading spectrometer can accurately detect the thickness of segregation layer.However,the process is cumbersome and expensive.It is difficult to accurately detect segregation layer by EDX analysis.Metallographic method can quickly and easily detect the thickness of segregation layer,which is the distance from the surface of ingots to coarse dendrite of ingot surface.关键词：4032 Alloy;Segregation Layer Thickness;EDX Analysis;Photoelectric Direct Reading Spectrometer
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发布时间：2023-12-18 - 摘要：Sand mould process was introduced for self-developed electro-driving transmission case with hybrid power.Al mould was man-made,and five sand moulds were assembled.Bottom-gating system with open structure was designed at the large plane.Through X-ray detection,absence of gas holes（shrinkage porosities）can be observed,meeting the quality requirement.关键词：Sand Mould Casting;Diesel Hybrid Transmission Case;Furan Resin-Bonded Sand
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发布时间：2023-12-18 - 摘要：Influences of trace Al on as-cast microstructures and mechanical properties of Mg-Gd-Y-Nd-Zr alloy were investigated at room temperature by XRD（X-ray diffraction）,SEM（scanning electron microscope）and tensile testing.The phase constituent,deposition change of the composition and fracture mode of the alloy prepared were analyzed.The results show that the as-cast Mg-Gd-Y-Nd-Zr magnesium alloy is mainly composed ofα-Mg matrix and equiaxed eutectic phase with the size of 40μm approximately.Meanwhile,the composition deviation of ingot in axial is very low,and grain size is uniformly distributed in the ingot.The composition distribution exhibits apparently changes after adding trace Al, and difference of the grain size between the top and bottom appears remarkably.In addition,the mechanical properties of the alloy with trace Al are varied with locations and less than those of the Mg-Gd-YNd-Zr.Alloy fracture mode is mainly characterized by brittle fracture along the grain boundary with obvious secondary cracks.With Al addition,Al2 RE and Al3 Zr phases can be observed in the alloy,resulting in the heterogeneous distribution of composition in the melt as a result of deposition and leading to the great coarseness of the grain size because of the decrease of Zr content at the top.Due to the generation of Al2 RE and Al3 Zr phases,as-cast microstructure is deteriorated and elongation is decreased,and alloy crack is characterized by brittle fracture.关键词：Rare Earth Magnesium Alloy;Solidification Segregation;Structure Analysis;Mechanical Properties
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发布时间：2023-12-18 - 摘要：Effects of low voltage pulsed magnetic field（LVPMF）on refinement of eutectic silicon in ZL108 alloy and its frictional properties were investigated.The results show that the eutectic silicon is refined significantly by LVPMF treatment,where eutectic silicon phase is transformed from coarse acicular structure into the co-existence of fine short fibre-like and particle-like ones with increasing in discharge frequency.The wear resistance of ZL108 alloy treated by LVPMF is significantly superior to that untreated by LVPMF.The analysis of worn surface indicates that wear mechanism of the ZL108 alloy untreated by LVPMF is characterized by adhesive wear and delamination wear,while it is mainly controlled by abrasive wear with slight adhesive wear in the ZL108 alloy treated by LVPMF.关键词：Low Voltage Pulsed Magnetic Field;ZL108 Alloy;Eutectic Silicon;Refinement;Friction Be-havior
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发布时间：2023-12-18 -
Microstructure of Al2Sm/AZ61 Magnesium Alloy Prepared by In-situ Reaction under Ultrasonic Treatment
摘要：The Al2 Sm/AZ61 magnesium alloys were prepared by ultrasonic in-situ reaction.And the microstructure and phase constituent of the alloys were investigated by means of optical microscopy（OM）, scanning electron microscopy（SEM）and X-ray diffraction（XRD）.The results indicate that with the ultrasonic power of 600 W for 2min,the Al2 Sm reinforcing phases size is reduced from 13μm to 6μm, and the agglomeration phenomenon is relieved.Discontinuous net-like Mg17 Al12 phase in AZ61-2Sm alloys is melted,meanwhile,the morphology of Al2 Sm phase exhibits the change from agglomerate state into small granular shape as a result of transient high temperature and high pressure from acoustic cavitation.Al2Sm particles are uniformly dispersed in the melt as a result of the acoustic streaming effect.关键词：In-Situ Reaction;Ultrasonic;AZ61-2Sm Magnesium Alloy;Microstructure- 2
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发布时间：2023-12-18 - 摘要：The ZCuSn10 tin bronze with equiaxed grain structure was prepared by strain induced melt activated method such as forging-remelting or rolling-remelting process.Firstly,ZCuSn10 tin bronze was poured,and samples were cut from ingot.Secondly,the samples were cool-rolled with two passes or four passes,or forged after holding at 450℃for 15minutes,then the samples prepared were heated up to 800℃ or 850 ℃for 10 minutes,and then quenched in water.The microstructure of the alloy prepared by SIMA method was compared with annealed microstructure and cast microstructure of ZCuSn10 tin bronze directly reheated then water quenched.The results indicate that equiaxed structure of ZCuSn10 tin bronze can be obtained by SIMA process,in which volume fraction of eutectoid structure is 16% at most.Comparing with annealed microstructure and cast microstructure of ZCuSn10 tin bronze directly reheated then water quenched,the average grain diameter is decreased to 8090μm from 250 300μm,and shape factor is decreased to 1.75 from 1.97.Deformation process plays a critical role in grain refinement and spheroidization during SIMA process for preparing the equiaxed structure of ZCuSn10 tin bronze.With deformation or remelting temperature increases,the size and shape of solid phase in microstructure of ZCuSn10 tin bronze are decreased and spheroidized increasingly,and volume fraction of eutectoid structure is increased.关键词：ZCuSn10 Tin Bronze;Strain Induced Melt Activation Method;Equiaxed Grains;Deformation Rate
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发布时间：2023-12-18 - 摘要：<正>20140301 Fragoso B,Santos H.旋转电磁场细化A354合金α-Al晶粒研究.International Journal of Cast Metals Research,2013,26（4）:193-200.晶粒细化是改善铝合金组织均匀性以及力学性能的主要手段之一,目前常用的晶粒细化方法包括:提高浇注温度、浇注前变质处理、外部处理（如搅拌和振动等）。在诸多细化方法中,电磁搅拌法由于其高效无污染、细化效果明显且便于操作的特点,成为最常用的晶粒细化方法之一。不过,电磁搅拌的晶粒细化机理还没有明确的定论。选择A354铝合金为研究对象,通过在
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发布时间：2023-12-18
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