最新刊期
卷 39 ， 期 10 ， 2019
- 摘要：The constitutive model and dynamic recrystallization behavior during thermal deformation of AZ80 magnesium alloy were investigated based on thermal compression testing.The effects of deformation parameters on the flow stress of AZ80 magnesium alloy were obtained by regression analysis on hyperbolic sine model,and the constitutive model of AZ80 alloy during thermal deformation was established.The relationship between critical strain of dynamic recrystallization and deformation parameters was described.Moreover,the dynamic recrystallization kinetic model was established based on the Avrami equation.关键词：Magnesium Alloy;Plastic Deformation;Constitutive Model;Dynamic Recrystallization
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发布时间：2023-12-18 - 摘要：The micro-arc oxidation ceramic layer was prepared by using the LA103 Zmagnesium-lithium alloy as the matrix in the silicate alkaline electrolyte,and its growth characteristics,microstructure and corrosion resistance were investigated.Micro-arc oxidation technique was used to prepare the coating layer at different current densities under constant oxidation time of 3 min,duty cycle of 10 and frequency of 500 Hz,.The micromorphology and thickness change of the ceramic coating were observed,respectively,by scanning electron microscope and coating thickness gauge.The corrosion performance of the coatings in 3.5% NaCl solution was analyzed by electrochemical workstation.At the same processing time,duty cycle and frequency,the increase of current density promotes the thickness increase of the ceramic layer with the maximum thickness of 25.65μm,and the weight increases of the coating with the maximum weight of 0.08 g,and the roughness of the coating layer is increased to 0.175μm.In addition,as the current density increases,the electrical insulation of the micro-arc oxidation coating layer presents more and more desirable,where the highest breakdown voltage can reach 0.63 V,and corrosion potential is positive than matrix at 27.8 A/dm2.关键词：Mg-Li Alloy;Micro-arc Oxidation;Micro-Morphology;Corrosion Resistance;Current Density
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发布时间：2023-12-18 - 摘要：<正>世界金属统计局（WBMS）近日公布的数据显示,2019年1～7月全球铜市场供应短缺2.7万t。7月末库存较2018年12月末高出14.4万t。这一增幅包括净付运至LME仓库的15.6万t和净付运至上海仓库的3.1万t。2019年前7个月COMEX铜库存下滑6.5万t。消费量统计中未包含未报告库存变动,尤其是中国库存。2019年1～7月,全球矿山铜产量为1 162万t,较去年同期低0.5%。2019年1～7月全球精炼铜产量为1 326万t,较去年同期减少3.2%,印度和智利产量显著减少,分别
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发布时间：2023-12-18 - 摘要：<正>近日,美国NioCorp公司、埃姆斯国家实验室和Tactical Alloys公司利用改进的冶金工艺成功生产出铝钪中间合金,有望成为潜在的中间合金商业生产途径。铝钪中间合金是将钪元素引入到铸造和锻造铝合金熔体之中,能够使铸造和凝固过程的晶粒细化,改善焊接性能,很大程度减少焊缝裂纹和失效,并提高合金抗拉及屈服强度,实现航空航天、汽车、船舶等平台的轻量化,降低能源消耗和碳排放。
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发布时间：2023-12-18 - 摘要：<正>世界金属统计局（WBMS）近日的数据显示,2019年1～7月全球锌市供应缺口为6 000t,2018年全年则为过剩6.4万t。1～7月期间报告库存增加1.1万t,上海仓库净增加2万t。7月LME库存再度下降,到7月末库存较2018年12月末低5万吨。LME库存占全球总量的14%,大多数金属存放在美国和荷兰仓库中。全球精炼锌产量同比增加0.7%,消费量则同比增加
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发布时间：2023-12-18 - 摘要：Effects of Zr on microstructure and biodegradation behavior of medical Zn-0.8 Mg alloy were investigated.The results show that the Zn-0.8 Mg alloy consists of primaryη-Zn phase and Mg2Zn11 phase,in addition,Zn22Zr phase can be observed with Zr addition.With the increase of Zr contents,the primaryη-Zn phase is coarsened gradually,and the average grain size is increased gradually from 102μm to 326μm,meanwhile,the volume fraction of Zn22Zr phase is increased gradually also.The corrosion rate and self-corrosion current density of the alloys are gradually increased with the increase of Zr contents,indicating that the degradation rate of the alloys in Hank’s solution is increased gradually.关键词：Zr;Zn-0.8Mg Alloy;Microstructure;Biodegradation Behavior
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发布时间：2023-12-18 - 摘要：Fe-based alloy layer was claded on 30CrMnSi steel by semiconductor laser cladding technology.The microstructure and phase structure of the laser cladding layer were analyzed by OM and SEM.The hardness,wear resistance and corrosion resistance of the laser cladding layer were tested.The results reveal that the microstructure of the Fe-based cladding layer mainly consists of fine and uniform equiaxed grains,which are mainly composed of Fe-basic,FeCr,FeNi,FeSi and FeB phase.And the surface microhardness of the cladding layer reach 718.8(HV0.1),and the wear resistance can be increased by more than 7 times compared with that of the base 30CrMnSi steel,so the corrosion resistance can be improved greatly.关键词：Laser Cladding;Microstructure;Corrosion Resistance;Wear Resistance
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发布时间：2023-12-18 - 摘要：Aiming at the automatic pouring of cast pipe,robot workstation was designed to realize the functions of intelligent pipe pulling,automatic cleaning,automatic spraying and intelligent transportation.An automatic control and monitoring system composed of Hollysys controller and Kunlun Tongtai touch screen was designed.The calculation and application results show that the static deformation of the robot beams is less than 0.3 mm,which meets the needs of engineering.The components run smoothly,and the logic of the control system is correct,and the production efficiency is increased by about three times.关键词：Seamless Steel Tube;Casting;Robot Workstation;Hollysys Controller
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发布时间：2023-12-18 - 摘要：The effects of surface temperature of different nucleation generators on the structure and mechanical properties of ferritic stainless steel ingots were investigated based on the vibration-induced liquid metal nucleation technology.The results reveal that with the increase of the surface temperature of the nucleation generator,the average grain size in the ingot obtained after nucleation experiment is decreased firstly and then increased,while the tensile strength,yield strength and hardness are increased firstly and then decreased.When the surface temperature of the nucleation generator is 500 ℃,the comprehensive properties of the ingot presents desirable,where the average grain size is 47.66μm,and the ambient tensile strength,yield strength and hardness reach 544 MPa,443 MPa and 149 HV,respectively.关键词：Surface Temperature;Ferritic Stainless Steel;Microstructure;Mechanical Properties
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发布时间：2023-12-18 - 摘要：<正>南京市溧水生态环境局于近日受理南京云海特种金属股份有限公司（"云海金属"）铝合金、铝中间合金及铝镁合金压铸和变形加工（一期工程）项目环评申请,并进行公示。项目位于南京市溧水区东屏镇工业集中区,一期规划年总产能25万t铝、镁合金及型材,项目总投资12亿元。资料显示,该项目分两期建设。本次项目为一期工程,占地面积15.09公顷,建筑面积逾10万m2,主要建设生产厂房、综合
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发布时间：2023-12-18 - 摘要：<正>近日,浙江万丰奥威汽轮股份有限公司（"万丰奥威"）控股股东万丰奥特控股集团有限公司（"万丰集团"）与中国宝武集团旗下的宝钢金属有限公司（"宝钢金属"）在上海签署了战略合作协议。万丰奥特控股集团陈滨总裁,宝钢金属有限公司党委书记、董事长贾砚林等参加签约仪式。根据万丰奥威公告,宝钢金属拟通过符合法律法规规定的方式成为公司重要股东,并与万丰集团展开在轻量化新材料等业务领域的全面合作。
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发布时间：2023-12-18 - 摘要：<正>应键战略是改变我们的日常交通方式。交通运输业排放气体约占全球温室气体（GHG）排放量的14%。虽然有多种多样的解决方案,但预计电动汽车（EV）将在减少污染方面发挥很大的作用。由于电动汽车依赖电力,因此相关排放量并非为零,除非电网本身是无碳电网。但国家可再生能源实验室最近的一项研究表明,即使在碳密集型电网中,电动汽车的使用产生的排放量也少于常规替代方案。对气候变化的一个关
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发布时间：2023-12-18 - 摘要：Filling and solidification process of aluminum alloy cylinder head with titling casting process were simulated by the Magma software,and relationship of the distribution of casting defects with filling velocity,air entrapment and solidification sequence in titling casting process were analyzed.The results were validated in actual production.In the subsequent optimization process,the porosity defects in the castings were eliminated by enlarging the feed riser,and the risk of porosity defects on the integrated exhaust side was reduced greatly by changing the tilting angle velocity from uniform speed to ladder speed,and the qualified rate of the castings reached to 96%.关键词：Aluminum Alloy;Cylinder Head;Tilting Casting;Numerical Simulation
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发布时间：2023-12-18 - 摘要：According to the current research situation of phase formation rules and alloying design of high-entropy alloys,two methods of designing alloys were reviewed.These methods are parameter calculation methods and computer simulation method.In the parameter calculation method,the effects of the mixing enthalpy,the mixing entropy,atomic size difference,the electronegativity difference and another parameters were summarized on the phase formation rules and alloy design of solid solution phase,TCP phase,amorphous phase and eutectic phases.In the computer simulation method,the methods of first principles calculation,molecular dynamics simulation and phase diagram simulation were summarized.关键词：High-entropy Alloy;Phase Formation Rules;Alloy Design;Parameter Calculation Method;Computer Simulation Method
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发布时间：2023-12-18 - 摘要：The ZL205A alloy samples were prepared by alternating magnetic field in vacuum differential pressure classification,and the relative density of the sample was characterized.The effects of the synergistic field on the relative density of ZL205A alloy sample were investigated.The results show that when the magnetic field strength is lower than 20 mT,the relative density of ZL205A alloy is improved greatly with enhancing the synergistic field effect.With the magnetic field strength higher than 20 mT,the relative density of ZL205A alloy sample is decreased with the increase of the classification pressure.Under the action of different synergistic fields,the relative density of the sample is decreased firstly and then increased along the casting direction.With the magnetic field strength of 20 mT and the grading pressure difference of 130 kPa,the relative density of the ZL205A alloy sample reaches a maximum value of 0.989 2,which is 0.38% higher than that of the first-stage pressure casting sample in the alternating magnetic field.关键词：Vacuum Differential Pressure Casting;Graded Pressurization;Alternating Magnetic Field;Relative Density
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发布时间：2023-12-18 - 摘要：The pedestal of DM3500 die casting machine was analyzed to reduce the high manufacturing cost.The variable density topology algorithm and size optimization algorithm were applied.Stiffness of the pedestal under four different working conditions was calculated through finite element analysis and was used as constraint condition for topology optimization.Based on the element density contour,18 steel plates can be removed.Further on,the optimization model of the pedestal was built,and by analyzing the element thickness distribution contour,the final optimized design was determined.As a result,the comparison with the original design under the same working condition indicates that the stiffness and strength of the new design pedestal reach design criteria with 5.98 t weigh reduction,which is 31.6% weight reduce rate.关键词：Ultra-large Die Casting Machine;Pedestal;Topology Optimization;Size Optimization
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发布时间：2023-12-18 - 摘要：The construction of intelligent manufacturing production management system was introduced by taking the product traceability of an aluminium die casting chain cover as an example to improve the ability to handle abnormal events quickly.Paperless production information management was realized gradually to replace a large number of human labor,and visual production process,comprehensive quality management,equipment and material management digitalization.关键词：Die Casting;Traceability;Intelligent Manufacturing Production Management System
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发布时间：2023-12-18 - 摘要：In order to optimize the extrusion casting process parameters and improve mechanical properties of the squeezing casting parts,the casting temperature（A）,extrusion pressure（B）and holding time（C）were selected as the optimization variables,tensile strength,hardness and elongation as response performance indicators.The response surface analysis method was adopted to establish the corresponding predictive regression model and carry out analysis of variance to obtain the affecting significance of various parameters and their interaction effects on the mechanical properties of the squeezing castings.The optimized combination of process parameters was obtained by using Design-Expert software as follows:pouring temperature of 750℃,extrusion pressure of 150 MPa and holding time of 21.37 s.关键词：Parameters Optimization;Response Surface Methodology;Squeeze Casting;Interaction Effects
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发布时间：2023-12-18 - 摘要：The structural characteristics,working conditions,material characteristics and technological requirements of the Al-Si alloy crossbeam for machine tool beam were analyzed.Based on the theory analysis of sand mould and metal mould low pressure casting,the reasonable semi-metal mould low pressure casting process was designed for the crossbeam.On this basis,the corresponding technological parameters were presented,and the simulation was carried out by the AnyCasting software.The results reveal that the process can not only meet the quality requirements,but also realize sequential solidification mode which is beneficial to the comprehensive performance of final castings by adjusting the position of outlet holes and cooling channels,reducing defects in castings,ensuring that the castings have the higher process yield and good quality.关键词：Crossbeam;Metal Mould;Low Pressure Casting;Sand Core;Simulation Analysis
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发布时间：2023-12-18 - 摘要：Based on the digital tool CimatronE,the die casting die design of watch case with side concave was described,including gating system,cooling system and ejection system,and reasonable design parameters were presented.The design method has an important role in shortening the die casting design and manufacturing cycle,reducing production cost and improving product quality.关键词：Zinc Alloy;Watch Case;Digital Design;Die Casting Die
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发布时间：2023-12-18 - 摘要：The effects of RE on microstructure,mechanical properties as well as the casting properties of AlSi7Cu4MgMn prepared by squeezing forging process were investigated.The results show that the RE can improve the casting properties and qualified rate of AlSi7Cu4MgMn alloy.The microstructure of AlSi7Cu4MgMn alloy is composed ofα-Al,eutectic Si phase,Fe,Al2Cu and other strengthening phases.The shape of Fe phase is changed from bulky structure into short stick with the RE addition.Meanwhile,the Al2Cu phase is refined and changed into AlxCu4Mg5Si4 complex phase.The mechanical properties of the alloy is weakened with excessive RE addition as a result of inducing Fe phase growth in the alloy.The RE can improve the mechanical properties of the alloy.The ultimate tensile strength,yield strength and elongation of AlSi7Cu4MgMn alloy reach 430 MPa,392 MPa and 6.8%,respectively,with 0.25% RE addition.关键词：Squeezing Casting;Rare Earth;Microstructure;Mechanical Properties
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发布时间：2023-12-18 - 摘要：The structure of ES11ZD upper cover was analyzed to design the initial die casting process.Then Flow-3D software was applied to simulate the initial scheme.The filling simulation reveals that filling process presents reasonable with the uniform temperature distribution.It is predicted that blow-hole can easily appear in the slender cylinder according to the distribution of entrainment gas.The initial scheme was improved by increasing the volume of overflow slots.The results show that the entrained air is decreased,however there still exists entrainment gas near the feeding gate.A chamfer was added at the connection between the feeding gate and the mold cavity in order to decrease the entrainment gas.Through using the optimized process design,the actual castings presents smooth surface with few defects.关键词：Upper Cover;Die Casting;Numerical Simulation
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发布时间：2023-12-18 - 摘要：The origination of dispersed shrinkage porosities（holes）as well as segregation in investment castings was analyzed.Through experiment analysis,two solutions of investment casting chilling process were put forward.The results show that the thicker areas of the casting can be cooled by the"I-beams"column block chill or inlaying block quenching process,and the castings can be rapidly solidified,thus avoiding shrinkage porosities（holes）and segregation defects,improving the production yield.关键词：Investment Casting;Cold Iron;Chilling Process
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发布时间：2023-12-18 - 摘要：The centrifugal radius of complex and small castings presents minuscule in centrifugal casting,which can often result in small centrifugal force to fill inadequately The mechanical properties of ZTC4 Ti alloy castings by rapid investment casting with vacuum gravity pouring were analyzed on the basis of optimizing the gating system.The results reveal that Polystyrene（PS）wax pattern with roughness less than 3.2μm prepared by selective laser sintering（SLS）technology can shorten greatly the development cycle.Gravity pouring impeller with vacuum degree of 4 Pa has a surface roughness less than 6.3μm,and X-ray detection presents defect free.The yield strength,tensile strength and elongation of the samples reach 805.67 MPa,922.67 MPa and 12.03%,respectively.The metallographic observation indicates that the homogeneous Widmanstatten structure is distributed in the alloy,meeting high-grade casting conforming to GB/T6614-2014 standard.关键词：Impeller;ZTC4Alloy;Rapid Investment Casting;Vacuum Gravity Pouring;Mechanical Properties;Microstructure
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发布时间：2023-12-18 - 摘要：The finite element model of solidification heat transfer analysis of 82 Bbloom was established by using finite element analysis software.The temperature field distribution of right-angle bloom and chamfer bloom during solidification process was calculated,and the solidification heat transfer mathematical model was established under the conditions of field technology and equipment.The results show that the angle temperature of the bloom produced by the chamfer mold is 62 ℃ higher than that of the right-angle bloom after exiting the mold,35 ℃higher than that of the right-angle bloom after exiting the secondary cooling zone,43 ℃ higher than that of the right-angle bloom after air cooling.In addition,the higher angle temperature can avoid the third brittle zone（700～900℃）of the steel,thus reducing the occurrence rate of corner cracks of the bloom in the straightening section and being also beneficial to the subsequent rolling process.In production,the desirable chamfer shape of chamfer bloom is chamfer angle of 35°and chamfer surface length of 50 mm.关键词：Numerical Simulation;Chamfer Shape;Bloom;Temperature Field
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发布时间：2023-12-18 - 摘要：A 3D FEM model of Al-7Zn-3Mg wrought aluminum alloy slab ingot with 450 mm×1 620 mm was established.Both thermal and stress fields of a slab billet were obtained via simulating casting conditions without wiper and with various wiper inserting positions,and the Clyne-Davies hot cracking model was used to calculate and evaluate the HCS（hot cracking susceptibility）of the ingots.The results reveal that the wiper has a little effect on both macrosegregation and HCSwhen it is placed at a height near the bottom of the solidifying end.The macrosegregation and HCSare increased greatly with the wiper setting position increases.When the wiper is inserted near the bottom of the sump,the macrosegregation and HCSof the billet are increased significantly.In order to suppress macrosegregation and hot cracking,it is suggested to insert the wiper at about 10 cm below the bottom of the sump.In contrast,the thermal stress of the ingot is decreased with the wiper setting position increases.In addition,the effect of an innovative stepwise wiper has also been analyzed.The results show that the new wiper can decrease the thermal stress by 4.5 MPa of the ingot than the conventional flat one and without negative effect on both macrosegregation and hot cracking tendency.关键词：Wiper;Aluminum Alloy;Macrosegregation;Hot Cracking;Cold Cracking
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发布时间：2023-12-18 - 摘要：The TiB/Ti-6Al-4V composites were prepared by SPS sintering.The effects of TiB2 addition on the microstructure and mechanical properties of the composites were investigated.The results show that the Ti-6Al-4V particles have not undergone significant deformation during the ball milling process,and the TiB2 is dispersedly embedded on the surface of Ti-6Al-4V particles.After SPS sintering,the matrix structure of the composite is changed from a sheet-like Wei′s structure to an approximately equiaxed structure due to the addition of TiB2.The TiB reinforcing phase formed by the reaction presents in the form of rods and whiskers,and it is distributed along the Ti-6Al-4V particles in a network.As the increases of TiB2 addition,the amount of TiB in the reinforcing phase is increased,and the strength and hardness of the composites are increased continuously.Compared with that of the sintered Ti-6Al-4V,the engineering strain of adding 1% TiB2 composite is increased and reached the maximum value.When the addition is more than 1%,the strain of the composite is decreased.关键词：TiB2Reinforcing Phase;Titanium Matrix Composite;TiB2 Addition;Microstructure
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发布时间：2023-12-18 - 摘要：2.5D shallow-bend joint woven Cf/Al composites with graphite fiber as reinforcement and ZL301 as matrix alloy were fabricated by the vacuum pressure infiltration method,and the ratio of warp/weft fibers of 2.5D shallow-bend joint woven preform was 54%∶46%,65%∶35% and 78%∶22%.The relative density,microstructure and mechanical properties of 2.5D shallow-bend joint woven Cf/Al composites with different ratio of warp/weft fibers were investigated.The results show that the relative density of 2.5D composites is decreased with the increase of warp fiber volume fraction,and the density of Cf/Al composites with warp/weft fiber ratio of 54%∶46%reaches the maximum value of 98.5%.Absence of infiltration defect in the microstructure can be observed,and it has the desirable infiltration effect.The ratio of warp/weft fibers has a great influence on the warp and weft tensile strength of 2.5D-Cf/Al composites.The 2.5D-Cf/Al composites with warp/weft fibers ratio of 65%∶35% have a warp tensile strength of 380.6 MPa and a weft tensile strength of 245.6 MPa,presenting the satisfied comprehensive properties.The tensile fracture surfaces are uneven and show a moderate interfacial bonding strength.关键词：Warp/Weft Fiber Ratio;2.5D Shallow-bend Joint Woven Cf/Al Composites;Vacuum Pressure Infiltration;Microstructure;Mechanical Properties
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发布时间：2023-12-18 - 摘要：To enhance the ambient mechanical properties of a CrFeCoNi high-entropy alloy,the alloying of 3%C（in atomic fraction）was performed.The alloys were subject to homogenization treatment at 1 200 ℃ for 12 h,cold rolling and recrystallization annealing at 800 ℃ for 1 h,obtaining fully recrystallized microstructures.The effects of carbide precipitation on the phase structure,microstructure,tensile behavior and corrosion behavior at room temperature were analyzed.The results reveal that after C alloying,spherical M23C6 carbides are precipitated besides of equiaxed-grained matrix with face-centered cubic structure,which are non-uniformly distributed on the grain boundaries and in the intragranular regions.The yield strength at room temperature is increased from 386 MPa of the CrFeCoNi alloy to 706 MPa of the C-alloyed one,however,the elongation and corrosion resistance are decreased to some extent.关键词：High-entropy Alloy;Carbide;Microstructure;Tensile Behavior;Corrosion Behavior
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发布时间：2023-12-18 - 摘要：The microstructure and mechanical properties of cast titanium alloy TA31 under different conditions at room temperature were investigated.And the mechanical properties of specimens after annealing treatment under room temperature were analyzed.Through experiment and actual application,the results show that TA31 alloy casting presents stable properties,where the tensile strength,yield strength,elongation and fracture contraction rate are more than 877 MPa,754 MPa,10.5% and 14%,respectively,meeting the specification and the operating requirement.关键词：TA31 Alloy;Microstructure;Mechanical Properties
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发布时间：2023-12-18 - 摘要：An optimization model of the metal casting process parameters for aluminum alloy was established to understand the interaction effects between process parameters on microstructure and casting defects in A357 alloy samples.Multi-objective optimization model was established to obtain the optimized solution of process parameters.The experiments design was established with the help of response surface methodology based on Box-Behnken design,where pouring temperature,mold temperature and the pouring time were taken as factors and equivalent particle size,average shaping factor and porosity volume were taken as response.The multi-objective optimization was carried out using NSGA-Ⅱ algorithm,and the optimization solution of process parameters was presented.Based on the optimized processing parameters,the experimental verification was carried out.The results show that the equivalent particle size and average shaping factor reach 298.69 "m and 0.532 with the decrease of porosity volume.关键词：Response Surface Methodology;Multi-objective Optimization;Process Parameters;Interaction Effect
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发布时间：2023-12-18 - 摘要：The Al-Mg-Si and Al-Mg-Si-Mn alloy strips with fine grains and homogeneous microstructure were prepared by the single roll melt rotating process,and the strip was prefabricated and hot extruded into densified bar at 500℃,and then it was treated by solid solution and artificial ageing treatment.The results reveal that the strip produced by the melt-spun method presents uniform structure with fine grain,and the tensile strength and yield strength of Al-Mg-Si-0.2Si alloy reach 227 MPa and 160 MPa,greatly increased compared with those of the AlMg-Si alloy,respectively,while the elongation remains above 20%.The addition of Mn can promote the formation of a new second phase MnAl6,which is nailed to the grain boundary,hindering the migration of subcrystals during the extrusion process,and thus inhibiting the dynamic recrystallization.In addition,certain amount of Fe in β-AlFeSi phases are replaced by Mn to form β-Al（FeMn）Si,resulting in the long-needle shapeβphase transforming into lumpyα-Al8（FeMn）2Si phase,relieving the harmful effects of Fe.At T6 state,Mn-containing dispersed phase formed in Al-Mg-Si-Mn alloy can inhibit the transition from small angle grain boundary to large angle grain boundary.In addition,new grain orientation and texture deflection occurr in both alloys,however <111> texture still is remained in Al-Mg-Si-Mn alloy,which may be attributed to the inhibition of sub-grain boundary migration by Mn-containing dispersed phase in original deformed texture during recrystallization,hindering the growth of recrystallized grains.Compared with Al-Mg-Si alloy,the Al-Mg-Si-Mn alloy is preferred to maintain its original orientation under heat treatment.关键词：Al-Mg-Si Aluminum Alloy;Melt-Spun;Al8（FeMn）2Si;MnAl6;Texture
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发布时间：2023-12-18 - 摘要：The effects of trace rare earth cerium on the as-cast structure of industrial pure aluminium were investigated,and the effects of cerium content on the electric conductivity of industrial pure aluminium were analyzed.The results show that rare earth cerium can refine the as-cast microstructure of industrial pure aluminium,and change the existing morphology of impurity phase in the microstructure and promote the spheroidization of impurity phase morphology.With 0.026% cerium addition,the electric conductivity of conductor is increased greatly,while with the content of cerium less than 0.142%,with the increase of cerium addition,the electric conductivity of the alloy is increased gradually.关键词：Trace Cerium;Pure Aluminium Conductor;Electric Conductivity;Grain Refinement;Spheroidization
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发布时间：2023-12-18 - 摘要：To improve the corrosion resistance of 45 steel,hot-dip aluminizing and anodic oxidation were adopted to prepare an anodic oxidation film with a certain thickness on the surface of the 45 steel.The effects of current density on the morphology,thickness and corrosion resistance of oxidation film were analyzed.The results reveal that the anodized coating of hot dip aluminized 45 steel is mainly composed of alumina layer,aluminized layer and aluminum-ferroalloy layer.Current density can affect significantly the thickness and morphology of the alumina film,so that the corrosion resistance of the oxidation film is affected.The thickness of oxidation film is increased with increasing in current density.Meanwhile,the size and area of the pores in surface of the alumina film are also increased with increasing in current density,therefore,the corrosion resistance of the composites is increased firstly and then decreased.After anodic anodized with a current density of 2.0 A/dm2 for 30 minutes,the self-corrosion current density of the hot-dip aluminized 45 steel in 3.5% NaCl solution is decreased by 2 orders of magnitude compared with that of ones before anodizing while the charge transfer resistance is increased by 20 times,indicating that the corrosion resistance is improved significantly.关键词：Hot-dip Aluminum;Anodic Oxidation;Oxide Film;Current Density;Oxidation Time
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发布时间：2023-12-18 - 摘要：The evolution of microstructure and texture,and their effects on the microhardness of high purity oxygen free copper tube during deformation were investigated by electron backscattered diffraction technology and hardness testing.The results reveal that for low strains,the microstructure is elongated along the axial direction,and the average grain size is decreased while the low angle grain boundaries are increased as strain increase,and thus the microhardness value is increased significantly.After deformation,there exists a major<111>fiber texture with a secondary<001> one paralleling to the axial direction.For high strains above 77%,both the grain size and low angle grain boundary are decreased slightly,and the microhardness is increased to some extent as the strain increase.The co-action of working hardening and the deformation result in the increase of<001>texture and<111>,which is great different from the conventional cases.The initial deformation is suggested to favor detwinining,while further deformation induces reappearing of twins.关键词：Oxygen Free Copper Tube;Texture;Twin;Microhardness
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发布时间：2023-12-18
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