最新刊期
卷 29 ， 期 2 ， 2009
-
-
-
-
-
-
- 摘要：Al-8.2Zn-2.1Mg-1.5Cu alloy containing 0.1%Pr was prepared by ingot metallurgy method.Effects of Pr addition on microstructure and mechanical properties of the alloy were investigated by OM（optical microscope）,mechanical property testing,scanning electron microscope（SEM）and transmission electron microscope（TEM）.The results indicate that grain size in as-cast alloy can be refined and recrystallization in as-extruded alloy can be restrained with 0.1% Pr addition,leading to the improvement of strength and fracture toughness of the alloy.The tensile strength and fracture toughness of the alloy with 0.1%Pr can reach 713MPa and 26.5MPa·m1/2,respectively.关键词：Al-Zn-Mg-Cu Alloy;Rare Earth Pr;Microstructure;Mechanical Properties
- 2
- |
- 85
- |
- 0
发布时间：2023-12-18 - 摘要：Amorphous Mg65Cu25-xNixTb10（x makes 0～10）rods with different diameters were prepared by conventional Cu mold casting method.Effects of Ni addition on the glass forming ability and mechanical properties of Mg-Cu-Tb amorphous alloy were analyzed by means of XRD（X-ray diffraction）,DSC（differential scanning calorimetry）,quasistatic compression testing and SEM（scanning electron microscope）.It is found that although it can decrease the glass forming ability and thermal stability of the alloy,appropriate Ni addition can greatly improve the fracture strength of Mg-Cu-Tb-Ni amorphous alloys,in which fracture strength of Mg65Cu20Ni5Tb10 can reach 943MPa,much higher than Mg65Cu25Tb10 alloy.关键词：Mg-based Amorphous Alloy;Glass Forming Ability;Elastic Modulus;Mechanical Properties
- 2
- |
- 95
- |
- 1
发布时间：2023-12-18 - 摘要：Microstructure and deformation mechanism of nano-crystalline Ni-Fe bulk alloy with 20 nm in average diameter which was prepared by electrodeposition were investigated by XRD（X-ray diffraction）,TEM（transmission electron microscope）and SEM（scanning electron microscope）.Meanwhile,uniaxial tensile testing by the MTS810 reveal that the alloy exhibits 2 GPa in strength and 8%～10% in strain,respectively.The nano-crystalline Ni-Fe alloy exhibits somewhat sensitive for strain rate,and grain growth in the alloy is controlled by plastic deformation mechanism,in addition,deformation twinning and dislocation movement have some effects on the grain growth also.In addition,abnormal growth of grain in the Ni-Fe alloy can be observed.It is found that plastic deformation of the nano-crystalline is related to the grain boundary activities.关键词：Nano-crystalline Ni-Fe Alloy;Mechanical Properties;Grain Growth;Deformation Mechanism
- 2
- |
- 144
- |
- 0
发布时间：2023-12-18 - 摘要：Effects of W on the unidirectional solidification structures of TiAl based alloy which was prepared by solidifying in a cold crucible after non-consumable arc melting were observed.The results indicate that dendrite in the TiAl based alloy can be greatly refined with W additon,in which grain size can be decreased to approximately 50μm with 2% W addition.With increasing in W addition,net-like W-rich phase appear in the primary β phase,and it is transformed into B2 phase.In addition,lamellar colony size can be decreased in the Ti-46Al alloy with W addition.关键词：TiAl Based Alloy;Unidirectional Solidification;W;Microstructure
- 2
- |
- 191
- |
- 2
发布时间：2023-12-18 -
-
-
-
-
-
-
-
-
-
-
-
- 摘要：Effects of Nd addition on microstructure and mechanical properties of AZ31 magnesium alloy were investigated by SEM（scanning electron microscope）and EDS（energy dispersive spectrum）.The results show that particle or acicular Al2Nd and Mg12Nd phase can be observed in AZ31 magnesium alloy with Nd addition.Al2Nd phase is prior to precipitating from the AZ31 magnesium alloy during solidification.With decreasing in temperature,divorced eutectoid Mg12Nd phase is precipitated,which results in the refinement of grain size in microstructure.The average grain size in alloy can be refined from 68μm to 29μm,and desirable tensile strength,yield strength and elongation are 245MPa,171 MPa and 9%,respectively,with 0.6%Nd addition.关键词：AZ31 Magnesium Alloy;Nd;Microstructure;Mechanical Properties
- 2
- |
- 224
- |
- 3
发布时间：2023-12-18 - 摘要：Effects of different temperature on re-deforming rate of cast-rolling AZ61 magnesium alloy strip were examined.The results reveal that the ultimate re-deforming rate of magnesium strip is more than 80% at 400℃ and 350℃,while it reaches 60% at 300℃ and it falls to about 40% at 250℃,furthermore,it drops down to 20%～30% at 200℃ and only 10% at room temperature.Deformed structure observation reveals that microstructure of cold rolled alloy is substantially similar to that of cast-rolling ones in range of ultimate re-deforming rate.Grain in rolled alloy at 200℃ exists in fibrous structure due to being elongated,and grain size can be evidently refined with rolling at more than 250℃.Grain with approximately 5μm in average size can be observed with rolling at 400℃.关键词：AZ61 Magnesium Alloy;Twin Cast-rolling;Re-deformation
- 2
- |
- 261
- |
- 1
发布时间：2023-12-18 - 摘要：Three kinds of aluminum anodes,including Al-Ga-In-Bi-Pb-Mg,Al-Ga-In-Cd-Mg and Al-Ga-In-Pb-Mg,were prepared.The self-corrosion rates of the alloys were tested by measuring corrosion weight loss,hydrogen evolution rates were measured by water immersion technique,electrochemical behavior was examined by electrochemical method,and surface morphology of corrosion alloys was observed by SEM（scanning electron microscope）.The results show that three aluminum alloy anodes have higher negative open circuit potentials,low self corrosion rates and low hydrogen evolution in the 5 mol/L solution.Moreover,with the increase of polarization potential,three anodes exhibit higher electrochemical activities.关键词：Aluminum Sacrificial Anodes;Corrosion;Electrode Potential;Electrochemistry
- 2
- |
- 160
- |
- 0
发布时间：2023-12-18 - 摘要：True stress-true strain of CuNiSi series alloys during hot compression deformation was drawn by isothermal compression testing at Gleeble-1500D thermal-mechanical simulator.Effects of temperature,deformed rate and alloying element on high temperature compression behavior of CuNiSi series alloy were approached.The results reveal that dynamic recrystallization is controlled by both strain rate and deformation temperature.With increasing in deformation temperature and decreasing in strain rate,dynamic recrystallization of the alloy is easer to take place,which results in the decrease of peak stress.In addition,flow stress of CuNiSiP is higher than that of CuNiSiAg alloy at the same condition.Deformation activation energy of CuNiSiP and CuNiSiAg alloy are presented.关键词：CuNiSiP Alloy;CuNiSiAg Alloy;Hot Compression Behavior;Dynamic Recrystallization;Thermal Simulation
- 4
- |
- 125
- |
- 2
发布时间：2023-12-18 - 摘要：Effects of added ways,such as direct addition and master alloy addition,on absorptivity of MM in die casting magnesium alloy were investigated.The results indicate that mistchmetal absorptivity is less than 50% by directly adding mistchmetal with melting at 720℃ in well type crucible furnace for less than 30 min.Mg matrix mischmetal can be prepared by casting combining with squeezing casting method,which exhibits Mg-RE metallic compound with various types and fine grain sizes from OM（optical microscope）analysis,and melting point is higher than die casting temperature from DSC observation,leading to fast solution velocity.The mistchmetal absorptivity can reach 94% and 96%,respectively,with adding mischmetal in as-cast ways and in extruded ways at 720℃ within 10 min in well type crucible furnace.Mischmetal absorptivity can reach up to 80% in die casting AZ91D magnesium in conventional cold chamber die casting machine with adding extruded master alloy,showing acceptable alloying process for RE element.关键词：Magnesium Alloy;RE;Die Casting;Adding Ways
- 2
- |
- 243
- |
- 1
发布时间：2023-12-18 - 摘要：Dendrite growth in directional solidification of succinonitrile-5% ethanol alloy was observed to examine effects of temperature and solute distribution.The results reveal that solute concentration in the dendrite interface which is in the middle area of two competitive growth can be increased with the drainage of solute in the process of dendritic growth in both sides,which results in more and more serious solute segregation in the middle dendrite so as to induce the necking effects.That dendrite in the middle area in multi-competitive growth dendrite appears in necking effects as a result of slow growth velocity is attributed to release latent heat from other dendrites growth,resulting in increasing temperature of middle area to form constitutional supercooling.Necking effects can be strengthened with increasing in liquid flow velocity at solid/liquid interface and in heterogeneity of temperature and solute distribution based on theoretical analysis,which is well in agreement with experimental ones.关键词：Directional Solidification;Real-time Observation;Analogue Alloy;Competitive Growth
- 2
- |
- 329
- |
- 5
发布时间：2023-12-18 - 摘要：Some defects,such as surface gas bubble and internal shrinkage hole in trial-production die casting Zn alloy faucet wrench were observed due to pouring-exhausting-flooding system designed by experience.So effects of structure and size design of pouring-exhausting-flooding system on filling and defects formation were analyzed based on wrench structure features and defects forming mechanism.Meanwhile,filling and defects formation in die casting were simulated by means of the Procast software.On the basis of simulated results,combining with die casting theory,design of pouring-exhausting-flooding system of the die casting die was optimized.The results indicate that surface gas bubble and internal shrinkage hole in the wrench can be greatly eliminated as a result of avoiding serious splash and eddy by adopting an expanding side runner with variable cross section and a wider ingate to obtain a desirable filling in cavity of wrench die with ratio of high length to width,meeting quality requirement for the castings.关键词：Die Casting Die;Pouring-exhausting-flooding System;Optimization Design;Numerical Simulation
- 2
- |
- 150
- |
- 5
发布时间：2023-12-18 - 摘要：Heterogeneous distribution of temperature field in mould and in wheel can be visualized by simulating temperature field of aluminum alloy wheel in low pressure casting using the ANSYS software.High temperature location in cavity can be examined by meshing the representative section of the cavity.Based on mentioned analysis,three kinds of optimized design were conducted and simulated.The results indicate that setting cooling channel and adjusting side-mould thickness as well as decreasing side-mould temperature,in which isolated island effects can be totally eliminated by decreasing side-mould temperature,can effectively eliminate isolated island effects.The practical production is well in agreement with simulated ones.关键词：ANSYS Software;Low Pressure Casting Mould;Temperature Field;Section;Optimization
- 2
- |
- 336
- |
- 5
发布时间：2023-12-18 - 摘要：Based on the principle of electromagnetic pump,design of electromagnetic field in electromagnetic pump was emphatically conducted.Effects of gas width and magnetic pole in divided electromagnet on magnetic induction intensity（B）were investigated.The results reveal that B has a linear relationship with square root of section area of iron core,and lnB has a linear relationship with gas width as well as center line circumference via square root of section area.The empirical calculation formula on B in a magnetic air gap for an open magnet in the saturated state was induced by a mathematical regression method.关键词：Aluminum Alloy;Casting;Electromagnetic Pump;Magnetic Induction Intensity
- 2
- |
- 133
- |
- 2
发布时间：2023-12-18 - 摘要：Permanent mold low pressure casting was used to produce aluminum alloy fuel-ejecting pump of diesel engines according to its structure and technical requirements.The processing parameters,including pouring temperature of（700±20）℃,filling velocity of 0.5m/s,filling pressure of 0.15MPa,holding pressure of 2.6MPa and holding time of 80s,were proposed.Practical production verifies that the designed low pressure casting mould has the advantages of convenient operation and reliable running,obtaining fuel-ejecting pump with satisfied quality.关键词：Pump;Permanent Mold;Low Pressure Casting;Mould
- 2
- |
- 298
- |
- 4
发布时间：2023-12-18 - 摘要：A pneumatic control system for differential-pressure casting equipment has been designed by analyzing structure of pneumatic control system.According to mentioned results,the Mitsubishi FX3U PLC was adopted to realize the automation of pneumatic control system,and the control system scheme was described.Meanwhile,according to the requirements and characteristics of pneumatic control system,the attribution of PLC’s I/O was confirmed,and the ladder diagram was designed.The main body of the PLC program utilizes stepping instruction to control every processing stages,evidently improving the system stability.关键词：Differential-pressure Casting;Pneumatic;Control System;PLC;Ladder Diagram
- 2
- |
- 235
- |
- 1
发布时间：2023-12-18 - 摘要：Al-9Gr semi-solid slurry was prepared by electromagnetic-mechanical stirring,and relationship between segregation of graphite particles and solid fraction in semi-solid slurry was determined.Technological condition of eliminating macro-segregation of graphite in the semi-solid slurry was obtained.The results show that with increasing in solid fraction in Al-9Gr semi-solid slurry,macro-segregation of graphite particles can be relieved.With solid fraction in semi-solid slurry more than 30%,macro-segregation of graphite particles is eliminated.关键词：Macro-segregation;Al-9Gr Semi-solid Slurry;Solid Fraction;Electromagnetic-mechanical Stirring
- 2
- |
- 131
- |
- 1
发布时间：2023-12-18 - 摘要：Black point defects in investment casting stainless parts were analyzed.Through adjusting gating system,setting filter screen at ingate to filter and purify liquid metal,and reducing ingate area or runner width,black point in the casting can be greatly eliminated.In addition,removal of residual wax should be completely cleaned,and rational deoxide operation should be noted in process of refinery and pouring.关键词：Black Point;Investment Casting;Gating System
- 2
- |
- 150
- |
- 1
发布时间：2023-12-18 - 摘要：Compared with common investment casting stainless steel components,defects including inclusion,over-weight,deformation easily appear in investment casting stainless steel golf head due to its complicated shape and high quality requirements for surface and internal area.These defects can be effectively eliminated by controlling wax pattern making,mold shell making,dewaxing and melting,pouring as well as clean,finishing,and so on.关键词：Golf Head;Investment Casting;Stainless
- 2
- |
- 223
- |
- 0
发布时间：2023-12-18 -
- 摘要：Two kinds of new casting technology for complicated aluminum alloy parts were described including investment casting-metallic mold and resin sand-investment casting compound mold.Aiming at structure features of aluminum alloy parts,different compound molds were used at different location of complicated aluminum alloy parts.It is an effective approach to produce complicated aluminum alloy castings by adopting compound mold technology and controlling microstructure and properties of different locations.关键词：Cast Aluminum Alloy;Compound Mold Investment Casting;Application
- 2
- |
- 411
- |
- 3
发布时间：2023-12-18 - 摘要：Three characteristics of V-EPC castings at home and abroad were reviewed,including co-development of large equipment and small equipment,the superiority in cast steel and nodular iron production as well as potential advantages in aluminum alloy and magnesium alloy product.Five technological breakthroughs of V-EPC at home were expounded including series and stadardization of EVA plastic film,development of large V-EPC molding line with independent intellectual property and independent innovation and improvement of V-EPC casting quality by means of CAD/CAM,control and energy-saving of vacuum system for V-EPC as well as application breakthrough of V-EPC in cast steel,nodular iron and aluminum alloy parts.However,there exist some problems,such as low machinery level,serious production circumstance and recarborization in low carbon stainless steel.关键词：V-EPC;EVA Plastic Film;Vacuum Control System
- 2
- |
- 705
- |
- 5
发布时间：2023-12-18 - 摘要：Effects of current intensity in electromagnetic stirring on microstructure and properties of continuous casting 30MnVS slab were investigated.The results indicate that with current intensity increasing from 50A to 250A,exquiaxed rate in the slab is increased by 53.3%,meanwhile,C and S elements in the slab are decreased by 50% and 14.3%,respectively,evidently improving segregation degree.With increasing in stirring current intensity,morphology of sulfides in the slabs is converted from rod-like structure into spheric and block structure with more uniform distribution,which is responsible for the improvement of mechanical properties of the slab as a result of improving the distribution of pro-eutectoid ferrite,where tensile strength and toughness are increased by 7.8% and by 24.4%,respectively.关键词：30MnVS;Electromagnetic Stirring;Current Intensity;Sulfide
- 2
- |
- 191
- |
- 8
发布时间：2023-12-18 - 摘要：Mechanical properties of fly ash micro-spheres reinforced aluminum matrix composites were examined by mechanical testing,and tensile fracture morphology was observed by SEM（scanning electron microscope）.The results indicate that tensile strength of the composites is superior to that of pure aluminum matrix.With increasing in fly ash micro-spheres addition,tensile strength is increased with decreasing in plasticity.Meanwhile,fracture morphology of the composites is converted from dimple rupture to cleavage fracture,exhibiting the transformation of plastic to brittle fracture.关键词：Aluminum Matrix Composites;Fly Ash Micro-spheres;Mechanical Properties
- 2
- |
- 129
- |
- 1
发布时间：2023-12-18 - 摘要：Al2O3/Cu-Cr composites with different oxygen resource（Cu2O）contents of 4%,5% and 6% were prepared by vacuum-pressed sintering with a simplified internal oxidation method.The microstructure and effects of cold deformation on properties of the composites were described.It is found that fine Al2O3 particles with diameters of 5～20nm and 20～150nm in particle interval were uniformly distributed into the Cu matrix.The hardness and tensile strength of the 80% deformed composites can be remarkably increased,while the electric conductivity of the composites is firstly increased and then decreased with increasing in deformation rate.With oxygen resource content increases,the soft resistance of the composites is strengthened.After hot-pressed sintering at 950℃ for 4 h in case of 22MPa,the internal oxidation of compressed Cu-Al alloy powder is totally completed with 5% oxygen resource content,resulting in the desirable comprehensive properties of deformed composites.关键词：Al2O3/Cu-Cr Composites;Hot-pressed Sintering;Properties;Electric Conductivity
- 2
- |
- 453
- |
- 4
发布时间：2023-12-18 - 摘要：Although reaction of SiO2 with liquid aluminum can occur at a certain condition based on thermodynamic analysis,it is difficult to make the reaction at temperature less than 1000℃ due to poor wettability between SiO2 and liquid Al.Effects of different pretreatment methods on SiO2 particle size were examined in Al-SiO2 reactive system,and reactive kinetics and finished product in the system were analyzed by DSC（differential scanning calorimeter）and XRD（X-ray diffraction）.The results indicate that the smallest SiO2 size with average diameter less than 1μm can be obtained after ball milling pretreatment.Wettability of SiO2 particle with liquid Al can be improved with decreasing in SiO2 particle size,which can decrease reactive temperature.Finished reactive temperature of SiO2 with liquid Al is less than 1000℃ with SiO2 particle size less than 2μm.关键词：Al-SiO2 Reaction;Particle Size;Reactive Kinetics
- 2
- |
- 177
- |
- 5
发布时间：2023-12-18 - 摘要：Microstructure and mechanical properties of Mg-0.6Zr alloys containing Er and Nd were investigated by optical microscope（OM）,scanning electron microscope（SEM）and energy spectrum analysis.The results reveal that mechanical properties of the Mg-0.6Zr alloy can be distinctly improved with Er and Nd addition as a result of grain refinement strengthening and solution strengthening.Grain size in microstructure of the alloy can be refined from 300 μm to 80 μm and 50 μm with Er or Nd addition.Tensile strength and elongation of the Mg-0.6Zr alloy with 0.94% Nd addition can be increased by 13.87% and 137.6%,respectively,with the slight change of yield strength,compared with those of matrix alloy,while those of the alloy with 1.09% Er addition can be increased by 11.16%,11.94% and 2.35%,respectively.Tensile strength of the alloy with mixed Er and Nd addition is equivalent to that of the alloy with Er addition,however,yield strength and elongation are somewhat declined.关键词：Mg-0.6Zr Alloy;Microstructure;Mechanical Properties;Er;Nd
- 2
- |
- 148
- |
- 4
发布时间：2023-12-18 - 摘要：Aluminum foam sandwich perform with high compact sandwich was prepared successfully by rolling-bonding method.Effects of rolling reduction on compactness and uniformity of the powders were analyzed,and deformed characteristics of sandwich was observed.The results indicate that compactness of sandwich powder in rolling-bonding process is greatly superior to that in hot pressing.Desirable rolling reduction is 65%,which can realize acceptable compactness and uniformity along width direction.The powders with irregular surface can contact each other with rolling pressure,which results in the occurrence of deformation and separation of particle surface bossing from the matrix.A large quantity of aluminum alloy powder particles with small size enriches in the interface zone of particles.关键词：Aluminum Foam Sandwich;Perform;Rolling-bonding;Compactness;Rolling Reduction
- 2
- |
- 181
- |
- 2
发布时间：2023-12-18 - 摘要：On the basis of empirical electron theory of solid and molecules（EET）,the valence electron structure（VES）of AlP and Si unite cell were calculated.Through comparing with the parameters of valence electron structure,it is concluded that the reaction of pure P atom or phosphide with Al atom in Al-Si molten can generate AlP particle which exhibits f.c.c structure and distribution of electron space similar to primary Si phase and low mismatching degree between AlP and Si unit as well as smaller nA value,so the AlP phase is prior to precipitating during the solidification to as heterogeneous nuclei of primary Si phase,increasing nucleation rate of primary Si phase.Calculated results confirm the theory of AlP phase as heterogeneous nuclei.关键词：Hypereutectic Al-Si Alloy;Modification;Primary Si;EET
- 2
- |
- 263
- |
- 2
发布时间：2023-12-18 - 摘要：Problems in vacuum sealed molding casting Al-Si alloy were described based on characteristics of the vacuum sealed molding and cast Al-Si alloy properties,including Al-Si alloy easier to oxidation and inspiration,high difference value of hydrogen solubility in between liquid aluminum and castings,slow heat radiation of vacuum sealed molding and high solidification contraction of Al-Si alloy.It is adopted to successfully produce Al-Si alloy high voltage switch by keeping the raw material properly to make a good preparation before melting and rapidly melting to decrease pouring temperature and time and raising cooling velocity and exhaust degree in cavity,fully refining as well as adopting tilting pouring.关键词：Al-Si Alloy;Vacuum Sealed Molding Casting;Casting;Problems
- 2
- |
- 170
- |
- 2
发布时间：2023-12-18 - 摘要：BFe10-1-1 alloy billets with 83 mm in diameters were prepared by horizontal continuous casting.Surface quality,microstructure and solute distribution of the BFe10-1-1 billets were described.The results indicate that the prepared billets exhibit smooth surface quality without oscillation marks.Macro-structure of prepared billets is composed of fine columnar grain in the edge and uniformly fine equiaxed grain in internal area,while microstructure exhibits the evolution characteristics of dense dendrite with orientation into equiaxed grain from edge to internal area.In addition,there exists solute element segregation to some certain in radial distribution of the prepared billets,and related countermeasures were put forward.关键词：Horizontal Continuous Casting;BFe10-1-1 Billets;Solidification Structure;Element Distribution
- 2
- |
- 291
- |
- 4
发布时间：2023-12-18 - 摘要：Effects of different RE additions including 0,0.04%,0.05% and 0.06% on the microstructure,mechanical properties and corrosion resistantance of the Zn-Al-Cu-Mg alloy were investigated.The results reveal that tensile strength and hardness of the Zn-Al-Cu-Mg alloy are increased by 11.8% and 5.6%,respectively,with appropriate RE addition as a result of refining grain size by restraining growth of dendrite.Meanwhile,corrosion resistance of the alloy can be slightly improved also.关键词：Zn-Al-Cu-Mg Alloy;RE Addition;Mechanical Properties;Corrosion Resistance
- 2
- |
- 120
- |
- 1
发布时间：2023-12-18 -
- 摘要：意德拉半固态流变压铸工艺与其他半固态压铸工艺的区别,在于它可以利用常规合金,使用现有的压铸设备和工艺,就能减少气孔、缩短压射循环周期时问并延长模具寿命。压铸件成本的降低不仅来自这些优势,还来自于减少的后序铸件的处理,例如取消浸渗和减少机加工。关键词：压铸;半固态流变压铸;意德拉
- 2
- |
- 156
- |
- 10
发布时间：2023-12-18 -
- Technical support is provided by Beijing Founder electronics co., LTD 京ICP备09064830号-19
京公网安备11010802024621 - It is recommended to read the content of this site in Chrome&IE9+. Please switch to extreme mode in browser 360.
- Cookies We use cookies to help provide and enhance our service and tailor content. By continuing, you agree to the use of cookies.
0