最新刊期
卷 32 ， 期 6 ， 2012
- 摘要：The dendrite structure characteristics,mechanical properties and forming conditions of Al-35La alloy prepared by directional solidification were investigated.The results show that the dendrite structure in Al-35La alloy obtained by directional solidification exhibits discontinuous and periodic two-phase morphology along the main body.The mechanic properties testing shows that the samples obtained exhibit higher compression strength and hardness.Formation mechanism of the periodic two-phase dendrite structure in Al-35La alloy was described.Convection with a certain intensity will take off crystallization latent heat in the liquid by promoting solute exchanging during nucleation and growth of dendrite.Therefore,it is considered that the convection with a certain intensity will promote the alternately nucleation and growth of two phase in the liquid of Al-35La alloy,resulting in the formation of periodic two-phase dendrite structure in the alloy.关键词：Al-35La Alloy;Periodic Two-Phase Dendrite Structure;Mechanic Properties;Alternately Nucleation
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发布时间：2024-04-01 - 摘要：The Sn-（8.98-x）Zn-0.02Al-xLa（x=0.02～0.12） solders were prepared by vacuum melting technique.Melting point,microstructure of the solder and its wettability on Cu substrate were analyzed through X-ray diffraction（XRD）,DTA（differential thermal analysis）,SEM（scanning electron microscope）.The results show that proper rare earth La can effectively increase the melting point of Sn-Zn-Al solder,and improve the spreading ability as well as homogeneity of microstructure.With 0.04%La addition,Sn-（9-x）Zn-0.02Al-xLa solders exhibit the desirable comprehensive properties.关键词：Pb-free Solder;Melting Point;Microstructure;Wettability
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发布时间：2024-04-01 - 摘要：The microstructures of as-cast AZ80-2.0Ca magnesium alloy were investigated,and effects of homogenizing treatment on microstructure evolution and hardness change of the alloy were analyzed by DSC thermal analyzer,optical microscope（OM）,scanning electron microscopy（SEM） and micro-hardness tester.The results show that the as-cast AZ80-2.0Ca magnesium alloy is mainly composed of α-Mg phase,β-（Mg17Al12） phase and（Mg,Al）2Ca phase.The melting point of β-（Mg17Al12） phase in the alloy is increased from 437 ℃ to 457 ℃ with Ca addition.The β-（Mg17Al12） phase is completely dissolved at 430 ℃ for 2 h,however,the（Mg,Al）2Ca phase is not dissolved at 430 ℃ for 24 h.In addition,the β-（Mg17Al12） phase is completely dissolved at 515 ℃ for 0.5 h,and the（Mg,Al）2Ca phase is decomposed and transformed into Al2Ca phase and Mg at 515 ℃ for 4 h,and then the Mg atoms are diffused into the matrix.However,the Al2Ca phase is not dissolved even though for 24 h.Micro-hardness of the alloy is decreased with the solution of the β-（Mg17Al12） phase and（Mg,Al）2Ca phase and it tends to be constant after decomposition completion.However,the micro-hardness of the AZ80-2.0Ca magnesium alloy after homogenization treatment at 515℃ is lower than that at 430 ℃.关键词：AZ80-2.0Ca Alloy;Homogenization;Microstructure;Hardness
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发布时间：2024-04-01 - 摘要：<正>位于河南省鹤壁市鹤山区鹤壁北站园区的鹤钢铸造有限公司一期年产4万吨钢铸件项目于5月12日投产。据了解,鹤钢铸造有限公司是鹤壁北站精密铸
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发布时间：2024-04-01 - 摘要：<正>在扶绥-崇左地区一水铝土矿勘查中,已探获一水铝土矿石资源量约8000万吨;在桂中经过对宾阳稔竹-王灵矿区等11个三水铝土矿普查项目的普查工作,预计探获高铁三水铝土矿资源量约
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发布时间：2024-04-01 - 摘要：<正>2012年5月9-12日,2012第十一届中国国际铸造博览会在北京召开。圣泉"一站式采购"的主题展示更是吸引了观众的眼球,成为展会的一大亮点。展台分为5个分区:大型铸铁件区、耐磨件区、汽车件区、铸钢件区、有色铸件区,每个分区都
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发布时间：2024-04-01 - 摘要：<正>"十二五"时期是我国材料工业由大变强的关键时期。今年年初,工业和信息化部发布的《新材料产业"十二五"发展规划》明确提出,加快镁合金制备及深加工技术开发,推进其在汽车零部件和轨道列车等领域的应用。预计到2015年,中国将形成15万吨高强镁合金压铸件及型材和板材的生产能力。
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发布时间：2024-04-01 - 摘要：<正>2011年中国各类铸件产量保持了一定增长,全国各类铸件总产量达到4150万吨,较2010年的3960万吨增长4.8%,增速放缓。整个"十五"至"十一五"期间中国铸件产量增长了2倍,不过进入"十二五"后,铸件产量增速放缓。
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发布时间：2024-04-01 - 摘要：<正>目前我国生产再生铜的方法主要有两类:第一类是将废杂铜直接熔炼成不同牌号的铜合金或精铜,所以又称直接利用法;第二类是将杂铜先经火法处理铸成阳极铜.然后电解精炼成电解铜并在电解过程中回收其他有用元素。用第二类方法处理含铜废料时,通常又有3种不同的流程,即一段法、二段法和三段法。
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发布时间：2024-04-01 - 摘要：<正>近日,"2012年中国企业家年会暨两江论坛"在重庆市隆重开幕,圣泉集团董事长、总裁唐一林荣获2011～2012年度"全国优秀企业家"荣誉称号,成为济南市首位获此殊荣的民营企业家。本次年会由中国企业联合会、中国企业家协会和重庆市人民政府共同主办,以"中国企业家:转型
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发布时间：2024-04-01 - 摘要：<正>2012年4月27日,国家工商行政管理总局商标局公布了在管理案件中认定的410件驰名商标,广东伊之密精密机械股份有限公司注册并拥有的"伊之密YIZUMI及图"榜上有名,其所覆盖的商品及服务包括了第七类中的压铸机和注塑机。
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发布时间：2024-04-01 - 摘要：<正>近年来我国精密铸造生产取得了大大的进步,我国已成为精密铸造制造大国。据不完全统计,一架飞机仅内饰件铸造就在200套以上,铸造件产值可达1亿元。现在相关企业针对飞机内饰件的材料选用、产品结构分析与设
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发布时间：2024-04-01 - 摘要：Effects of minor Zr additions on the microstructure and mechanical properties of super-high strength Al alloys by spray forming were investigated by optical microscope（OM）,scanning electron microscope（SEM） and transmission electron microscopy（TEM）.The results show that there exists coarse non-dissolve phases with the size from 5 μm to 30 μm and the strip-like morphology in the alloys with Al-Zr master alloy addition.The size of coarse phases is increased with the increase of Zr in the master alloys.Absence of coarse phases in the alloys with the Zr addition in form of pure particles can be observed.The fracture analysis shows that the coarse phases are the initiation resource of cracks,leading to the deterioration of the mechanical properties severely.The tensile strength and elongation are 820 MPa and 5%,respectively,of the alloy with the Zr addition in form of pure particle while their are 710MPa and 3.5%,respectively,of one with Zr addition in form of Al-Zr master alloys.关键词：Spray Forming;Mechanical Properties;Microstructure;Master Alloys
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发布时间：2024-04-01 - 摘要：Tungsten coating with 1mm in thickness was fabricated on copper alloys by means of vacuum plasma sprayed and by air plasma sprayed technology,respectively.And the properties of the coatings prepared were analyzed comparatively.The results show that vacuum plasma sprayed tungsten coatings exhibit the lower porosity and impurity content,a higher transfer-heat capability and the better bonding strength as well as heat flux performance.Therefore,vacuum plasma sprayed tungsten coating is more suitable for plasma facing material in fusion device,compared with air plasma sprayed coatings.关键词：Plasma Sprayed Technology;Tungsten Coating;Fusion
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发布时间：2024-04-01 - 摘要：Laval-like funnel cap spraying gun was developed based on the theories of aerodynamic.The modified spraying gun could atomize micro-drop under the supersonic state to form finer metal particles.And the effects were compared with those of WDP2000-I spraying gun.The results show that the granularity is more dense,finer and more uniform.Average granularity is decreased by 41.3% for spraying Zn powders by the modified gun,and it is decreased by 29% for spraying Zn-Al powders.The particle beam is more dense in the modified gun,which can increase deposition efficiency,save spraying materials and improve the efficiency of electric arc spraying tooling.关键词：Laval-Like Funnel Cap;Electric Arc Spraying;Rapid Tooling;Supersonic State
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发布时间：2024-04-01 - 摘要：The Mg-6Al-1Ca-1Nd alloy samples were fabricated by centrifugal casting method and by gravity casting,respectively.The microstructure and mechanical properties of Mg-6Al-1Ca-1Nd alloy fabricated were characterized by OM（optical microscope）,SEM（scanning electron microscope）,XRD（X-ray diffraction） and hardness testing.The results show that the grain size of Mg-6Al-1Ca-1Nd alloy exhibiting equaixed grain fabricated by centrifugal casting is finer than that fabricated by gravity casting.With increasing in centrifugal speed,the grain size is decreased.The XRD analysis shows that there exists Mg17Al12、Al2Nd and Al2Ca phases and α-Mg in the Mg-6Al-1Ca-1Nd alloy fabricated by centrifugal casting.However,absence of Al2Ca phase can be observed,and the content of Mg17Al12 and Al2Nd is decreased in the Mg-6Al-1Ca-1Nd alloy fabricated by gravity casting.With increasing in centrifugal speed,the hardness value of the alloy fabricated by centrifugal casting is increased,and with the centrifugal speed of 1 541 r/min,the hardness value reaches HV58.5.关键词：Centrifugal Casting;Magnesium Alloy;Microstructure
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发布时间：2024-04-01 - 摘要：The casting and forging compound process of Al alloy was developed for the trial-manufacture of rear steering knuckle（an automobile part）.With the help of casting simulation software Adstefan and forging simulation software Deform,casting and forging processes were simulated and optimized,respectively,during designing process.In addition,mechanical properties and microstructure of the steering knuckle samples produced were investigated.The results show that the casting and forging compound process is a practical and effective method for making some automobile parts.关键词：Steering Knuckle;Casting;Forging;A356 Alloy
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发布时间：2024-04-01 - 摘要：Finite element analysis of ANSYS was applied to analyze the relation between the deformation conditions and the strain states of the die and sample during ECAP,and to understand the deformation rules of the sample.Severe deformation was taken place during the corner of the channel,exhibiting large deformation gradient,which leads to the occurrence of end effects.It is necessary that the sample is long enough to keep a stable deformation section in order to obtain an acceptable result.Higher extrusion speed should be considered owing to its less effects on the ECAP.关键词：Equal Channel Angular Pressing;Al-5Ti-B;Numerical Simulation
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发布时间：2024-04-01 - 摘要：The collapsibility of different proportion of alkali phenolic resin sand with the silica sand at 100 500 ℃ was investigated,and the lowest temperature is 400 ℃ when the mold is totally collapsed.The solidification process and the temperature field of the mold and core in cylindrical steel castings with different wall-thickness were simulated by the Procast software.The relationship between the wall thickness（module） of cylindrical steel castings and the critical mold thickness of the alkali phenolic resin sand was described,and the regression equation was presented.关键词：Alkali Phenolic Resin Sand;Steel Castings;Collapsibility;Critical Mold Thickness
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发布时间：2024-04-01 - 摘要：<正>由中国铸造协会主办的"2012第十届中国铸造协会年会"5月8日在北京九华山庄会议中心盛大启幕。原全国人大常委、中国铸造协会名誉理事长郭树言受邀出席了会议,工业和信息化部副部长苏波为年会发来贺信,1073名代表参加了此次年会。
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发布时间：2024-04-01 - 摘要：<正>中国机械工程学会铸造分会质量控制及检测技术委员会拟于2012年10月上旬在四川乐山召开第十届学术年会,热情邀请国内外有关企业、研究、设计院所、高校的专家、学者、铸造工作者等参加和撰写论文,现将征文有关事项通知如下。
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发布时间：2024-04-01 - 摘要：Semi-solid 5083 alloy slurry was prepared by a self-developed double ultrasonic field treatment device,and effects of inclined channel、ultrasound power and different arrangement of double ultrasonic field treatment devices on the solidification structure were investigated.The results show that inclined channel and ultrasound power can improve the grain number and its morphology.The 5083 alloy slurry with finer and spheroidized grain can be prepared by treatment device with staggered double vibration heads.关键词：Double Ultrasonic Field;5083 Alloy;Semi-solid;Microstructure
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发布时间：2024-04-01 - 摘要：Effects of processing parameters on microstructure and Cu distribution in squeeze casting Al-5Cu-0.4Mn alloy were investigated.The results show that primary α-Al grain size in the alloy is significantly refined with solidification under a pressure of 25 MPa.Coarse microstructure is increased with increasing in pouring temperature.Non-uniform and coarse microstructure is formed with increasing in mould preheating temperature.Normal solute concentration profile can be observed in the squeeze casting alloy rather than inverse segregation under gravity casting Cu content is increased from the edge to the center.That is attributed to solute-rich driven to the inside of the castings through skeleton channel of inter-dendrite by forced feeding of pressure.The average solubility of Cu in α-Al matrix is increased with the increase of applied pressure.Cu content in primary α-Al grain rises with radius distance of the specimen.Sound squeeze castings of Al-5Cu-0.4Mn alloy with fine grain structure and less macro-segregation can be obtained with a pressure of 100MPa,pouring temperature of 680～730 ℃,and die temperature of 200 ℃.关键词：Squeeze Casting;Microstructure;Solute Distribution;Al-Cu Alloy
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发布时间：2024-04-01 - 摘要：There exists surface flash,scratch and size over-tolerance on the die casting pin-shaped insert.Surface flash on the insert can be eliminated by using fast-pin and spring for pressing insert.Scratch on the insert surface can be avoided by setting drafting angle at hole for assembling insert in the mould to make the un-direct contact of effectively working position of the insert with hole at the mould.To prevent the insert from the mould automatically,magnetic iron was set in die casting die to ensure the fixation of iron insert in the mould.关键词：Die Casting Die;Insert;Insert Dimension;Flash;Magnetic Iron
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发布时间：2024-04-01 - 摘要：Structure of ETC throttle valve body,mould structure and scrap occurred in the production were introduced.The feeding system and exhausting system were modified.The injection pressure was decreased by enlarging chamber from 50 mm to 60 mm in diameter.Practical running parameters were measured.It is found that the real injection velocity is lower far away designed parameters.Through adjusting injection velocity,the scrap was decreased.关键词：Assisted Pouring Channel;Exhausting System;Processing Parameters Measurement
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发布时间：2024-04-01 - 摘要：The structure characteristics of the engine cylinder head and its process were described.Bottom big plane for assembly benchmark was set as the parting face.Inlaid structure was adopted in the whole set mould with oblique spigot position.Cross-section of the splash pieces was set as the meniscus form,which could effectively prevent liquid metal along the exhaust slot splash.3D structure of movable mold,cover die,gating system and exhaust system were presented.关键词：Engine Cylinder Head;Die Casting Die;3D Design;Aluminum Alloy
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发布时间：2024-04-01 - 摘要：Effects of glass fiber addition on the viscosity of the ceramic slurry and the tensile strength of ceramic green body for investment casting were investigated.Ceramic green body is mainly made from quartz sand and silica sol,and glass fiber is approximately 16 μm in diameter and 13 mm in length.The results indicate that,with a certain amount of glass fiber addition,tensile strength of the samples is increased with the temperature increases.Within a certain range,the tensile strength of the ceramic mold is increased linearly from 0.175 MPa to 0.221 MPa with increasing in glass fiber sintered at 400 ℃,and the viscosity of ceramic slurry is increased in an exponential form.关键词：Ceramic Mold Casting;Glass Fiber;Tensile Strength;Viscosity
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发布时间：2024-04-01 - 摘要：Through analyzing the cooling characteristics of the silica shell,based on hydrodynamic equations,it is derived that the liquid steel during filling process and the heat exchange time between ingate wall is proportional to the liquid steel in ingate,which affects the over-heat of flow channel near the ingate,resulting in occurrence of shrinkage porosity.The mass flow density is adopted to check area and number of ingate.It is acceptable for mass flow density less than 0.4×104 kg/m2.Application of the mass flow density in the heat riser,ladder,bottom-pouring,multi-ingate,and composite gating system as well as balance pouring,hot flow channel was presented to effectively eliminate the shrinkage porosity in ingate and flow channel.Due to having considered parts weight in application of mass flow density in ingate,the parts on the assemble tree are not fall out as a result of large weight of parts with small hot spot size and small total ingate area.关键词：Sol Silicate Mold Shell;Mass Flow Density;Ingates;Gating System
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发布时间：2024-04-01 - 摘要：The coating which was made of alumina,quartz powder and mica as refractory materials,bentonite of natrium and CMC as compound deflocculant,polyvinyl alcohol（PVA） as agglomerant was developed for lost foam casting ductile iron pipe.The performances of the coating prepared were measured.The results show that the coating developed exhibits good performance,meeting production requirements.关键词：Lost Foam Casting;Refractory Coating;Performance Test;Ductile Iron
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发布时间：2024-04-01 - 摘要：In order to obtain the whole austenite microstructure in the as-cast ZGMn13 steel,ZGMn13 samples with addition of muti-alloy elements and solidification process control were prepared by vacuum-evaporation pattern casting（V-EPC）.The microstructure features before and after alloying were analyzed by optical microscope（OM）,X-ray diffraction（XRD）,X-ray fluorescence analyzer and hardness testing.The results show that with alloy elements of 0.33Cr-0.38Mo-0.06V-0.05Ti-0.66 Ni（weight,%）,a part of precipitation of carbides in the steel can be observed,however,with alloy elements of 0.72Cr-0.70Mo-0.14V-0.13Ti-1.23Ni（weight,%）,totally as-cast austenite microstructure can be presented in the steel.With the increase of alloy elements addition,change of as-cast solidification microstructure is absent.The austenite grain size are decreased and hardness is increased with the increase of alloy elements,respectively.关键词：As-cast High Manganese Steel;Alloying;Single Phase Austenite;Solidification Structure
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发布时间：2024-04-01 - 摘要：<正>据报道,巴基斯坦费萨拉巴德供电有限公司（FESCO）首席执行官Tariq Mehmood Chattha说,为了更加有效节约地扩大电力系统的分布以及降低电线被偷盗的损失,公司将优先把铝导线用来替代昂贵的铜导线。
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发布时间：2024-04-01 - 摘要：<正>据俄罗斯生意人报报道,俄罗斯称自己是大西洋底最大的黄金和铜储备所属国之一。俄罗斯自然资源部报告说,联合国国际海底管理局已经认可俄罗斯于2010年12月提出的关于俄罗斯在大西洋底进行地质调查的申请。这项计划是为了开发世界上最大的尚未开发的海域,其中
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发布时间：2024-04-01 - 摘要：<正>5月14日,欧洲媒体Euractiv报道,欧委会正在制定一项法规草案,拟允许成员国对14个高耗能行业因参与排放权交易系统ETS而增加的用电成本进行特殊补贴。初步行业名单包括:铝业,化工和肥料矿产品开采业,无机化工业,铅、锌、锡生
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发布时间：2024-04-01 - 摘要：Effects of rare-earth Nd additions including 0,0.4%,0.8% and 1.2% on microstructure and mechanical proeprties of as-cast and hot-rolled Mg-3.5Zn-0.6Y alloys were investigated,respectively.The results show that the grain exhibits fine equiaxed crystals in the Mg-3.5Zn-0.6Y alloys with 0.4% and 0.8% Nd addition,and the second phases Mg41Nd5 and Mg24Y5 can be observed in the microstructure.The second phases are crushed during hot-rolling,resulting in the finement of grains.The tensile strength and elongation of as-cast Mg-3.5Zn-0.6Y-0.4Nd alloy with annealing at 400 ℃ for 12 h and of hot-rolled one with annealing at 400 ℃ for 0.5 h reach up to 234 MPa,265 MPa and 14.6%,11.7%,respectively.关键词：Mg-Zn-Y Alloy;Microstructure;Tensile Strength
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发布时间：2024-04-01 - 摘要：Effects of 0.12%Sr and different RE addition,such as 0,0.12%,0.24%,0.36%,0.48% and 0.60%,on microstructure and mechanical properties of ZL101 alloys with 1.2% Fe were investigated by optical microscope（OM）,X-ray diffraction（XRD）analysis,and INSTRON5882 EUMTS.The results showed that at a fixed Sr addition,the morphology of β-Fe phases in ZL101 alloys can be obviously improved with RE and Sr compound addition,and its structure is converted form needle-like into fine short rod.In the meantime,α-Al grains are refined and eutectic silicon is transformed into granular in the alloy after T6 heat treatment.The proper RE can improve mechanical properties of Al-Si alloys with high Fe content modified by Sr,and the increase of elongation is very slight.With addition of 0.36% RE +0.12% Sr in the alloys,the tensile strength of alloy after T6 heat treatment can reach the maximum 213 MPa,increased by 26.8% compared to 168 MPa of corresponding as-cast alloy.关键词：RE;Sr;Microstructure;ZL101 Alloy;Mechanical Properties
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发布时间：2024-04-01 - 摘要：The as-cast microstructure of AZ31 magnesium alloy can be refined with 0.3%～0.6% MM（mistchmetal）,and mechanical properties of the alloy prepared are improved after hot extruding process.Tensile strength,elongation of the extruded alloy at room temperature reach 285～300 MPa and 16%～21%,respectively.However,with MM addition more than 0.6%,the tensile strength and elongation of the extruded alloy are decreased slightly.关键词：MM;Hot Extrusion;AZ31 Magnesium Alloy;Microstructure and Properties
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发布时间：2024-04-01 - 摘要：The temperature measurement of molten Al alloy in main frequency furnace was conducted by the infrared technology instead of the thermo-couple and protection sleeve.The working principle of the infrared technology was introduced,and the main technological features and the key technology were described.The feasibility of the measuring method was analyzed,and the related technological requirements were presented.The practical application verified that the infrared technology could be applied for the temperature measuring of the molten Al alloy in the main frequency furnace.关键词：Infrared Temperature Measurement;Aluminum Alloys;Induction Furnace
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发布时间：2024-04-01 - 摘要：Magnesium alloy exhibits poor plastic performance,therefore,the plastic forming of magnesium alloys becomes a new technical challenge.Continuous rheo-extrusion forming realizes magnesium alloy from high-temperature liquid directly into finished products,reducing procedures and saving energy.However,there often appears cracks on the upper and lower surfaces of the products.Origination of crack formation was analyzed.The different liquid metal velocity is responsible for the crack formation in the alloy products.Through using lubricant agent,controlling extruding rate and enlarging fixed-radial length of the mould,the crack is eliminated.关键词：Magnesium Alloy;Rheoforming;Crack
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发布时间：2024-04-01 - 摘要：Effects of different degassing processes on molten aluminum and on the modification efficiency of different modifier with Na and Sr were investigated.The results show that the rotating-injection argon gas degassing technology combining with the salt degassing can improve the molten aluminum degassing efficiency,and the rotating-injection argon gas degassing technology combining with the Na salt refining process can decrease the H2 absorption during refining process.In addition,the rotating-injection argon gas degassing technology can reduce the strontium burning in the molten aluminum,improving the modification efficiency of strontium.关键词：Aluminum Alloy;Degassing;Modification;Compound Treatment
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- 337
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发布时间：2024-04-01 - 摘要：Effects of Cu addition on the solidification structure of Zn-27Al alloy were investigated.The phase transition and the microstructure distribution of the alloy with different Cu addition were analyzed through observing microstructure and dendrite morphologies using X-ray diffraction,Electro-probe microanalyzer and scanning electron microscope.The results show that the Cu-enrichment phase ε with dispersedly distribution in the microstructure is gradually converted into CuZn4 phase which is enriched on dendritic arm of α-Al phase with the increase of Cu addition.And the microstructure in Zn-27Al alloy is gradually transformed from the coarse equiaxed grains into developed dendrites,and to the columnar dendrites with big length-diameter ratio,and then to the dendrites with the developed secondary branches and relatively short primary arm.关键词：Cu Addition;Feathery Dendrite;Phase Transformation
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发布时间：2024-04-01 - 摘要：Effects of 0.3%～0.9% Mg on the microstructures,mechanical properties and machinability of P-Ca brass with lead-free have been investigated.Through observing the microstructures and detecting properties,it is found that Mg can inhibitor the generation of the lamellate intermetallic compound,improving the machinability distinctly with the slight change of strength and hardness.Meanwhile,the elongation can be increased significantly.However,with the content of Mg more than 0.6%,the elongation is deteriorated sharply.P-Ca brass with 1.0%P,0.2%Ca and 0.6%Mg exhibits appropriate mechanical properties and machinability.关键词：Lead-Free Brass;Magnesium;P-Ca Brass;Microstructure;Properties
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- 110
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发布时间：2024-04-01 - 摘要：Through analyzing fracture morphology of line breaking in ultra-fine copper wires during drawing process,origination of line breaking was approached.Some defects are responsible for the occurrence of line breaking,such as gas hole,porosity,inclusion,surface defects and inadequate plasticity in the copper wire billets,and uneven copper line deformation,large deformation force,loss of tool as well as precision and stability of the equipment.Based on defects analysis and practical production,countermeasures were presented.Through optimizing raw materials and mould,and selection of lubricant as well as equipment optimization,occurrence of line breaking can be significantly decreased,realizing the normal production of copper wire.关键词：Ultra-Fine Copper Wire;Line Break;Process Optimization
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- 313
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发布时间：2024-04-01 - 摘要：<正>曾侯乙编钟（下页见）战国（公元前475年-前211年）早期钟架长748cm,宽335cm,高273cm,重4400kg高锡青铜湖北随州出土湖北
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发布时间：2024-04-01
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