最新刊期
卷 40 ， 期 11 ， 2020
- 摘要：Carbon fiber reinforced Al-matrix composites have great potential in a wide range of applications due to their high specific strength, specific modulus,low coefficient of thermal expansion and good impact toughness.In view of the bottleneck problem of poor wettability between molten Al and carbon fiber, the effects of surface coating technology of carbon fiber on the wettability and infiltration behavior were discussed. The characteristics of various fabrication processes was summarized. Different interfacial enhancement mechanisms and their effects on the interfacial failure behavior and mechanical properties of the composites were analyzed.关键词：Carbon Fiber;Al-matrix Composites;Fabrication Process;Interfacial Enhancement
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发布时间：2023-12-18 - 摘要：The effects of secondary aging stress on electrochemical corrosion of Al-Zn-Mg-Cu aluminum alloy（7 A04）with two-stage stress aging were investigated in 3.5%NaCl solution by polarization curves and electrochemical impedance spectroscopy.The results indicate that with the increase of the stress in 0～300 MPa,the corrosion potential of 7 A04 aluminum alloys is increased and then decreased,while the self-corrosion current density is varied to the contrary.The alloy possesses the best electrochemical corrosion resistance with the aging stress of200 MPa,where the corrosion potential is-0.753 Vand the self-corrosion current density is 5.249×10-7 A·cm-2.Compared with stress-free and single-stage stress aging,the corrosion potential and AC impedance of 7 A04 aluminum alloy with two-stage stress aging are the higher and the self-corrosion current density is the lower,while its effect on pitting corrosion potential is not obvious.The change of precipitation phase distribution and size in 7 A04 aluminum alloy after stress aging are responsible for improving its electrochemical corrosion resistance.关键词：7A04 Aluminum Alloy;Two-stage Stress Aging;Electrochemical Corrosion;Corrosion Mechanism
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发布时间：2023-12-18 - 摘要：The rapid development of aerospace and automobile fields strongly demand low-cost, high-quality and high-performance aluminum alloys. Aluminum components prepared by squeeze casting exhibit outstanding advantages, such as compact structure, weak anisotropy, few casting defects and high mechanical properties. At present, the development of alloys suitable for squeeze casting with proprietary intellectual property rights and their production processes is the key to development of squeeze casting. Characteristics of various squeeze casting methods such as direct squeeze casting, indirect squeeze casting and semi-solid squeeze casting was analyzed comparatively.Moreover, squeeze cast aluminum alloys were categorized, which could provide references for the preparation of high-performance squeeze cast aluminum alloys. Finally, the challenge in the development and key points in the research of squeeze cast aluminum alloys were pointed out.关键词：Squeeze Casting;Aluminum Alloy;Casting Defects;Microstructure;Mechanical Properties
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发布时间：2023-12-18 - 摘要：<正>深圳市科达利实业股份有限公司公告,为了进一步拓展海外市场,满足公司战略发展需要,公司拟在匈牙利投资设立全资子公司并以自有资金不超过3 000万欧元（1欧元=7.794人民币——本刊注）投资建设科达利匈牙利生产基地一期项目。
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发布时间：2023-12-18 - 摘要：The influences of different Al content on the damping performance of pure magnesium were investigated. The results show that with a lower Al addition, the Al atoms mainly exist in form of solid solution atoms and it will not significantly reduce the damping behavior of the magnesium alloy, while with a higher Al content, a second phase Mg17Al12 can be observed in the alloy to refine the grains, meanwhile the damping performance of the alloy is greatly reduced. The critical damping strain of the alloy is increased with the increase of Al content. In heating damping, the Mg-0.25 Al alloy has dislocation peaks and grain boundary internal friction peaks at 60 ℃ and 260 ℃, respectively. The increase of Al solid solution atoms will hinder the appearance of damping peaks.关键词：Magnesium Alloy;Damping Properties;Solution Atoms;Dislocations
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发布时间：2023-12-18 - 摘要：Ultrasonic treatment of Al-6.2 Cu-0.36 Mn alloy melt at 710℃ was carried out. The comprehensive effects of ultrasonic treatment with different durations on hydrogen content, grain size, morphology and distribution of eutectic structure in Al-6.2 Cu-0.36 Mn alloy were investigated. The results show that with the increase of ultrasonic treatment time, the porosity in the solidified microstructure of the ingot is reduced with the degassing efficiency up to 53.8%, meanwhile, the grain is obviously refined and the refinement rate is up to 73.6%. In addition, the agglomerated eutectic microstructure is transformed into discontinuous strips. The effect of cavitation and acoustic flow caused by ultrasonic vibration can raise the nucleation rate and promote the uniform distribution of solute, which is the main reason for the improvement of solidification structure of the Al-6.2 Cu-0.36 Mn alloy ingot.关键词：Ultrasonic Treatment;Al-6.2Cu-0.36Mn Alloy;Hydrogen Content;Grain Refinement;Eutectic Structure
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发布时间：2023-12-18 - 摘要：TiC-reinforced β21 S titanium alloy matrix composites were prepared with electric arc furnace smelting using SiC as the raw material. The influence of the content of SiC（0, 0.2% and 0.4%） on microstructure and properties of β-titanium alloy-based composites was analyzed. In addition, the effect of heat treatment on microstructure and properties of deformed composites was also expounded. The results show that in-situ precipitated TiC precipitated presents a slender strip. With the increase of SiC content, the precipitated TiC becomes short. The existence of TiC phase can significantly increase the hardness of the β21 S alloy. When SiC addition is 0.4%, the hardness of the composites reaches 484 HV. After deformation and solution-aging treatment, the elongated TiC phase is decomposed and spheroidized into small granular TiC phases. The dispersed TiC phase can greatly inhibit the formation and movement of dislocations, thereby further increasing the hardness of the β21 S alloy. After solution treatment at 840 ℃ for 20 min and aging at 600 ℃ for 8 h, the hardness of the 0.4% SiC-added composites is increased by 4 times compared with the as-cast state, reaching 2 572 HV.关键词：β21S Matrix Composite;TiC;In-situ Synthesis;Deformation-heat Treatment;Hardness
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发布时间：2023-12-18 - 摘要：Based on the structural features of the current electromagnetic braking（EMBr） configuration, a new type of EMBr was proposed, which can be applied to the thin slab continuous casting process, namely Vertical-Combined Electromagnetic Braking（VC-EMBr）. The multiple behaviors of metallurgical in CSP funnel-shaped mold were numerically simulated under the brake of VC-EMBr through ANSYS FLUENT commercial software. The results indicate that the horizontal magnetic poles of VC-EMBr can reduce the penetration depth of molten steel and promote the floatation and removal of inclusions. The vertical magnetic poles of VC-EMBr can suppress the molten steel surface velocity and improve the homogeneous temperature distribution in the mold region, which accelerate the uniform growth of solidified shell, and then achieve the metallurgical effect of electromagnetic braking.关键词：Electromagnetic Braking;Thin Slab Continuous Casting;Temperature Distribution;Solidified Shell
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发布时间：2023-12-18 - 摘要：AZ31 B Mg alloy samples after finish turning processing were treated by using HK30 C USRP machine, and effects of different rolling rate on microstructure of the AZ31 B alloy were analyzed. The results indicate that the surface roughness of 0.100 9 μm is decreased by 91.8% compared with the untreated specimen（Ra=1.232 6 μm）. The severe plastic deformation in the surface of AZ31 B is formed by USRP, and the grains in the surfaces layer of AZ31 B are remarkably refined. The microstructure in surface region of the USRPed specimens is presented as nanostructure whose average grain size is decreased by 98% compared with the interior grains, and the depth of the grain refinement in surface layer after USRPed reaches about 270 μm. Meanwhile, the surface microhardness is increased by 117.14% compared with the interior ones. The wear resistance of AZ31 B Mg alloy samples is significantly improved after USRP. The friction coefficient is decreased from 0.337 to 0.279. The mass loss is reduced from 32.44 mg to 9.07 mg. The surface roughness reduction, grain refinement and extreme plastic deformation caused by USRP are responsible for promoting the hardness and wear resistance of AZ31 B Mg alloy.关键词：AZ31B Mg Alloy;Ultrasonic Surface Rolling Process;Microstructure;Wear Resistance
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发布时间：2023-12-18 - 摘要：The corrosion behaviour of 2 A12 aluminum alloy in marine environment was simulated based on the COMSOL. The results show that the pitting corrosion occurrs under the action of Cl- at the beginning of the corrosion. Subsequently, the corrosion is developed into intergranular corrosion at 175 h, and eventually evolved into comprehensive corrosion with the advance of the reaction, which is completely corroded at 280 h. However, the corrosion rate is significantly increased in model containing the IMP. The corrosion is developed into intergranular corrosion at 75 h, and finally evolved into comprehensive corrosion, which is completely corroded at 240 h. A large amount of Al（OH）3, which is generated by electrochemical corrosion, is deposited on the surface of the pit, preventing the contact between electrolyte and substrate and thus inhibiting corrosion. Simulation results show that with prolonging corrosion time, the self-corrosion current density of 2 A12 alloy is decreased firstly and then increased until the corrosion is end.关键词：2A12 Aluminum Alloy;Marine Environment;Corrosion;Simulation;COMSOL
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发布时间：2023-12-18 - 摘要：<正>2020年10月份,制造业PMI为51.4%,虽略低于上月0.1个百分点,但自7月份以来始终位于51.0%及以上,已连续8个月处于扩张区间,制造业总体持续回暖。本月主要特点:一是产需保持较快恢复。生产指数为53.9%,比上月微落0.1个百分点,新订单指数为52.8%,与上月持平,均持续位于临界点以上,表明制造业生产继续回升,需求稳步改善。从行业情况看,部分传统制造业恢复有所加快,其中,纺织、化学纤维及橡胶塑料制品、黑色金属冶炼及压延加工、有色金属冶炼及压延加工、金属制品等行业生产指数和新订单指数较上月均有不同程度上升。
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发布时间：2023-12-18 - 摘要：<正>近日,世界上首个使用再生铝生产的船舶专用码头充电桩外壳成功实现应用。据悉,该产品由海德鲁的再生铝品牌CIRCAL为船舶专用码头充电网络——Vita Super Power提供,产品中至少有75%材料为回收后的废铝再利用。
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发布时间：2023-12-18 - 摘要：<正>近日,生态环境部、海关总署、商务部、工业和信息化部联合发布《关于规范再生黄铜原料、再生铜原料和再生铸造铝合金原料进口管理有关事项的公告》。为规范再生黄铜原料、再生铜原料和再生铸造铝合金原料的进口管理,推动再生金属产业高质量发展,现将有关事项公告如下:
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发布时间：2023-12-18 - 摘要：<正>为进一步完善排污许可技术规范体系,生态环境部发布《排污许可证申请与核发技术规范金属铸造工业》（HJ1115-2020）等5项技术规范,全面推进排污许可制度改革。目前,5个行业排污许可证申请与核发功能近日即将正式上线,届时相关行业排污单位可在全国排污许可证管理信息平台中正式申报排污许可证。
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发布时间：2023-12-18 - 摘要：<正>（1）铝矾土2020年9月中国进口铝矾土约为836.59万t,同比上涨23.95%;出口铝矾土约为0.126万t,同比下降45.74%。（2）氧化铝2020年9月中国进口氧化铝约为35.47万t,同比上涨139.97%;出口氧化铝约为0.41万t,同比下降87.97%。（3）无水氟化铝2020年9月中国无水氟化铝进口量为19.8t,同比下滑12%。进口总价为135 759美元。9月无水氟化铝出口量为8 276.6t,同比下滑3.52%。出口总价为9 503 675美元。
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发布时间：2023-12-18 - 摘要：The current application and development status of iron-based materials at home and aboard was summarized, focusing on corrosion resistance of molten aluminum. The approaches and related mechanisms to improve the corrosion resistance of molten aluminum were described from the aspects of alloy elements, surface modifications and thermal treatments.Finally, based on the existing technical achievements of the researchers, it is planned to propose future design, improvement thoughts and key research directions for developing a new type of high-quality and inexpensive iron-based materials resistant to corrosion in molten aluminum or significantly improving the corrosion resistance of existing materials.关键词：Molten Aluminum Corrosion;Iron-Based Materials;Alloy Elements;Surface Modifications;Thermal Treatments
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发布时间：2023-12-18 - 摘要：The applied underwater acoustically transparent materials were classified and summarized in detail according to the related literature. The relevant performance requirements of acoustically transparent materials of the sonar dome were expounded firstly. Then the types of underwater acoustic materials and related research results were summarized. Finally, the development prospects of underwater acoustically transparent materials were put forward.关键词：Underwater Acoustic Engineering;Underwater Acoustic Detection;Acoustically Transparent Material;Acoustically Transparent Property
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发布时间：2023-12-18 - 摘要：Numerical simulation technology was used to analyze the extrusion load, temperature field, equivalent strain field and microstructure of TC4 titanium alloy in the process of equal channel angular pressing at different conditions. The results show that with the increase of extrusion temperature, the plasiticity of the TC4 alloy is increased, while the deformation difficulty and the load required for extrusion are reduced. In the process of extrusion speed increasing, the variation of maximum equivalent strain value becomes more sensitive, which is decreased fast with the increase of extrusion speed. Through multi pass extrusion deformation, the maximum equivalent strain is even multiplied, and the accumulated plastic deformation of the specimens is increased, with the significant grain refinement effect. Overall, the grain refining effect is optimized under the extrusion temperature of 350 ℃, extrusion rate of 4 passes and extrusion speed of 0.5 mm/s.关键词：Finite Element Simulation;Titanium Alloy;ECAP;Grain Refining;Multi-pass
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发布时间：2023-12-18 - 摘要：The numerical simulation method was used to understand the smelting process of the stainless steel micro-melt pool under the laser during the selective lasermelting process. The effects of laser power, spot diameter and laser loading time on the fluid motion in the micro-melt pool were investigated. The results reveal that increase of laser power and reduction of the spot diameter can effectively reduce the height of fluid vortex and increase the flow velocity of fluid. The molten pool can reach the stableflow state with using a spot diameter of 200 W, 20 μm or 400 W, 40 μm as the heat source.关键词：Selective Laser Melting;Micro Melting Pool;Vortex Height;Flow Velocity
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发布时间：2023-12-18 - 摘要：ProCAST software was used to simulate the mold filling and solidification process based on a theoretically designed gating system for obtaining a reasonable camshaft cap die-casting mold. The results show that the 6-runner scheme can result in multi-flow confluence, causing gas entrapment and shrinkage defects, while a 5-runner scheme can reduce the gas and internal porosity in die castings.The locations and volume of the pores were predicted by simulation of solidification, shrinkage holes（porosities）, and then an optimized scheme removing an overflow groove was proposed, which could significantly shorten the solidification time. X-ray inspection and cutting surface of the key position of the die-cast castings show that absence of shrinkage hole in the product can be observed. The efficiency of mold design can be improved by die-casting simulation, and the production efficiency as well as product quality can be enhanced though pouring system optimization.关键词：Aluminum Alloy Camshaft End Cap;Die Casting Die;Gating System;Numerical Simulation;ProCAST Software
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发布时间：2023-12-18 - 摘要：In order to trace and optimize the factors influencing the quality of low-pressure casting,the dimension of the factors affecting the quality characteristic values was reduced using principal component analysis to obtain the principal components of the influencing factors. Then, the principal components were subjected to variance analysis and interaction analysis using response surface methodology to establish a regression model, and the response surface graph and the contour line of the main interaction factors were drawn. Finally, the values of the influencing factors ensuring the quality characteristic value optimal were presented as follows: the mold temperature of 300 ℃, the holding pressure time of 88.56 s, the crystallization pressure of 0.043 MPa, the liquid lifting speed of 130 mm/s, the pouring temperature of 710 ℃, the coating thickness of 1.7 mm, the mold preheating temperature of 220 ℃, the filling speed of 50 mm/s, and the Si content in the molten metal of 7.1%.关键词：Low Pressure Casting;Principal Component Analysis;Multivariate Analysis of Variance;Response Surfacemethodology
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发布时间：2023-12-18 - 摘要：Aiming at the casting defects in the die casting aluminum alloy components, the effects of Al-5 Ti-1 B refiner on aluminum melt were analyzed. It is found that shrinkage hole, shrinkage cracks at local wall-thickness or internal casting defects such as shrinkage porosities can be observed in the aluminum alloy die castings without Al-Ti-B refiner modification treatment, while the alloy with Al-5 Ti-1 B refiner modification treatment, the defects in the alloy can be improved greatly. In addition, the mechanical properties of the alloy with Al-5 Ti-1 B refiner modification treatment are superior to those of one without Al-5 Ti-1 B modification treatment.关键词：Al-Ti-B Master Alloy;Shrinkage Porosity;Shrinkage Holes;Die Casting;Mechanical Properties
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发布时间：2023-12-18 - 摘要：The difference in microstructure of Al-5 Ti-0.2 B,Al-5 Ti-1 B and Al-3 Ti-1 B grain refiners, and the effects of the three refiners on the grain refinement of large-sized 7050 aluminum alloy and the properties of 7050-T7451 state thick plate were investigated. The results reveal that TiAl3 phase in three refiners is mainly distributed as a block with a size of 15～50 μm, while TiB2 phase is a small particle with a size of 1～2 μm and easy to aggregate irregularly. The TiAl3 phase content in the three refiners is 8.16%, 5.60% and 1.45%, respectively. The refining effect of Al-5 Ti-1 B refiner is the desirable, with the core size of 87 μm and edge size of 60 μm.Meanwhile, the 7050 alloy thick plate with Al-5 Ti-1 B refiner has the satisfied mechanical properties, and the tensile strength, yield strength and elongation reach up to 555 MPa, 505 MPa and 14.8%, respectively.关键词：Refiners;Grain Refinement;7050-T7451 State;Mechanical Properties
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发布时间：2023-12-18 - 摘要：The numerical simulation software ProCAST was used to simulate the initial casting process of the K423 alloy liner castings. The distribution and causes of shrinkage porosities in the castings were determined by porosity criterion and temperature field analysis. The casting process design was improved based on the simulated results. Through small batch production, it is found that the castings produced by the improved process has the obsence of defects under X-ray detection and the relative density reaches 99.8%.关键词：K423 Alloy;Casting Process Optimization;Feeding Channel;ProCAST;Relative Density
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发布时间：2023-12-18 - 摘要：A new type of fast investment casting process was proposed via 3 D printing wheel investment and gypsum casting, in view of the existing problem that traditional casting, low pressure and casting spinning, and forging process were not suitable for individual production. A top-injection pouring system was applied to design relative processing parameters, and then a finite element modelling was employed to prove the feasibility of a certain process program. Finally, non-defective Al-alloy wheel was produced by gypsum casting, which provided a new process for the customization of individual wheel in a small batch.关键词：Aluminum Alloy Wheels;Investment Casting;3D Printing;Top-injection Pouring;Simulation
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发布时间：2023-12-18 - 摘要：During the development process of 50 MW heavy duty gas turbine blade of DongFang Steam Turbine, 3 D printing resin blades was used to obtain accurate casting shrink factor which helps to constructe the wax mold. Moldflow software was firstly introduced into wax mold design and the simulation result shows that cold wax core can effectively reduce the non-uniform shrinkage which control the size of wax within the tolerance range. Sintered shell dimension was inspected by ATOS digital scanning of dissected shell and an innovation way was provided to analyze shell deformation. The casting results show that the shrinkage rate of the wax is set reasonably and the cold wax core process and molding process is contributed to ensure the final casting size.关键词：Gas Turbine Blade;Investment Casting;Wax Pattern;Deformation;Simulation
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发布时间：2023-12-18 - 摘要：In order to understand the friction and wear properties of NiCr coatings with different Al2O3 mass fraction, the NiCr coatings with Al2O3 mass fraction of 10%, 15% and 20% were prepared on the surface of valve steel by laser cladding technique. The microstructure, element composition, phase, hardness, friction coefficient and wear volume of different coatings were analyzed by scanning electron microscopy, energy spectrometer, X-ray diffractometer, microhardness tester and high temperature friction and wear testing machine, and the wear mechanism of different coatings was explored.The results show that the surface hardness of the three groups of coatings is obviously improved, and the average friction coefficient reaches 0.152, 0.114 and 0.095, respectively.The coating surface with Al2O3 mass fraction of 10% presents slight plastic deformation, obvious adhesive wear and local oxidation.The surface plastic deformation of the coating with Al2O3 mass fraction of 20% is serious, accompanied by slight oxidation wear and microcrack.The coating with an Al2O3 mass fraction of 15% has the minimum wear volume, with only slight adhesive wear and oxidation wear.关键词：NiCr Coating;Laser Cladding（LC）;Al2O3 Mass Fraction;Coefficient of Friction（COF）;Wear Volume
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发布时间：2023-12-18 - 摘要：IC10 single crystal Ni3Al-based superalloy and GH3039 superalloy can be used in the manufacture of integral leaf disc by electron beam welding. The effect of welding parameters on microstructure and mechanical properties of GH3039/IC10 electron beam welded joints was investigated by changing welding speed, which provided data references for practical application of the project.关键词：Superalloy;Electron Beam Welding;Microstructure;Mechanical Properties
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发布时间：2023-12-18 - 摘要：The lead-free and free cutting 2011 aluminum alloy bars were prepared by Bi and Sn substituted for Pb. The effects of Bi content on microstructure, mechanical properties and cutting properties of 2011 aluminum alloy bar were investigated by metallographic microscope, scanning electron microscope, tensile testing machine and high-speed lathe. The results reveal that Bi mainly exists in form of BiSn eutectic phase in aluminum alloy bars when the Bi content is 0.2%. When the content of Bi is more than 0.2%, Bi exists in form of Bi phase and BiSn eutectic phase. The higher the Bi content is, the more the amount of Bi phase and BiSn eutectic phase are, so the cutting performance of aluminum alloy bar is improved and the chip length is decreased. However, the tensile strength and elongation of aluminum alloy bar are decreased slightly with the increase of Bi content. When the Bi content is increased to 1%, the average chip length of aluminum alloy bar, the tensile strength and the elongation are 3 mm, 283.5 MPa and 25.9%,respectively.关键词：2011 Aluminum Alloy;Extrusion;Bi Element;Cutting Performance
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发布时间：2023-12-18 - 摘要：During the trial production of an integrated exhaust manifold aluminum cylinder head, a serious shrinkage defect was observed the threaded hole position of the inlet and exhaust side on the large end face of the timing side, and the rejection rate reached up to 26%. The solidification process of the casting was simulated by the AnyCasting software, and the origination of the defect was analyzed. The simulated results indicate that the hot spot is formed due to local thickness of the shrinkage, and then shrinkage cracking occurs during solidification, which leads to shrinkage defect.Therefore, some improvement measures were taken including the adding water-cooled inserts into the mold at the porosity position and setting up a riser, and absence of shrinkage defect was found in the continuous production of 30 cylinder heads.关键词：Aluminum Cylinder Head;Gravity Casting;Shrinkage Porosity;AnyCasting Software
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发布时间：2023-12-18 - 摘要：The effects of forming pressure and hold-pressure time on the microstructure and mechanical properties of the high strength and toughness Al-5 Mg-2 Si-Mn alloy were investigated by OM and SEM.The results show that with the forming pressure of 100 MPa for 10 s, the average grain size and shape factor of α-Al in the alloy can reach up to 29.59 μm and 0.76 respectively, and the Mg2Si phase is mainly dispersed in the form of dots or rods with the obvious inbihition of the precipitation of intermetallic compounds. Meanwhice, the tensile strength and elongation of the alloy is increased from 185 MPa and 3.1% in gravity casting to 312 MPa and 13.5%, increased by 68.6% and 335.5%, respectively.关键词：Al-5Mg-2Si-Mn Alloy;Forming Pressure;Holding Pressure Time;Microstructure;Mechanical Properties
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发布时间：2023-12-18 - 摘要：The defects of 7055 aluminum alloy flat ingot were analyzed by means of optical microscope and scanning electron microscope. The results indicate that the 7055 aluminum alloy flat ingot has segregation tumor enriched Zn and Cu element, which has a bad influence on flat ingot quality. The formation mechanism of segregation tumor was analyzed, and the improvement measures were put forward to prepare high quality ingot without obvious segregation tumor defect.关键词：7055 Aluminum Alloy Ingot;Segregation Tumors;Formation Mechanism;Process Improvement
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发布时间：2023-12-18 - 摘要：Cu-2 Ag alloy wire rod was prepared by three chamber vacuum cold mold vertical drawing continuous casting technology. The effects of different drawing deformation on microstructure, mechanical properties and electrical conductivity of Cu-2 Ag alloy were investigated. The results reveal that the as-cast microstructure of Cu-2 Ag alloy wire rod is mainly distributed in the form of dispersed "spinning cloth" dendrites. With the increase of deformation, the grains are gradually refined and broken, and the cross-section microstructure is extruded and twisted, so the grain boundary becomes fuzzy. Fiber structure is formed in the longitudinal section. With the increase of deformation, the fiber grain spacing is decreased, and the outer fiber structure spacing is smaller than the core. The tensile strength is increased rapidly from 205 MPa to 594 MPa, the elongation is decreased from 38%to 3.5%, and the electrical conductivity is decreased from 53.418 MS/m to 50.750 MS/m through multi pass continuous drawing. SEM fracture analysis shows that the fracture mode is characterized by dimple fracture into shear fracture.关键词：Multi Pass Continuous Drawing;Cu-2Ag Alloy;Deformation;Microstructure and Properties
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发布时间：2023-12-18 - 摘要：The effects of Fe-based amorphous alloys on microstructure and properties of the as-cast QAl9-4 aluminum bronze were studied. The results reveal that the phase composition of QAl9-4 aluminum bronze with Fe-based amorphous alloy or pure iron is α+β′+k,however, the former is smaller and more uniform. The tensile strength、Brinell hardness and elongation of QAl9-4 aluminum bronze with Fe-based amorphous alloy are 589 MPa、141 HB、29.9%,increased by 21.8%、15.0% and 9.9% compared with those of ones with pure iron, respectively. In addition, the main wear mechanism of the two alloys are characterized by abrasive wear and adhesion wear,and the wear resistance of QAl9-4 aluminum bronze with Fe-based amorphous alloy is more satisfied.关键词：Fe-based Amorphous Alloys;QAl9-4 Aluminum Bronze;Wear Resistance
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发布时间：2023-12-18 - 摘要：Sn-1.0 Ag-0.5 Cu-0.06 Sm lead-free composite solders were prepared by mechanically mixing method. The effects of creep on the matrix microstructure and interface morphology as well as mechanical properties of Cu/Sn-1.0 Ag-0.5 Cu-0.06 Sm/Cu solder joints were investigated by SEM, EDS and bond strength tester. The results reveal that under the action of long-term high temperature creep, Ag3Sn and Cu6Sn5 phases can be continuously precipitated in the matrix structure of the solder joints, which is merged, grown and aggregated. The morphology of the IMC layer continuously is grown from a scallop shape in the reflow state to a relatively flat and thick layer, and transformed from Cu6Sn5 single phase to two phases of Cu6Sn5 and Cu3Sn, resulting in decrease of 21.3% in the tensile strength of the solder joint compared with that of the reflux state.关键词：Sn-1.0Ag-0.5Cu;Lead-free Solder Joint;Creep;IMC
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发布时间：2023-12-18 - 摘要：The effects of Co addition on the electrical conductivity, hardness and corrosion resistance of Cu-Ni-Si alloy were investigated. The results show that the electrical conductivity of alloy is increased by adding 0.1%Co, and the excessive addition of Co leads to the decrease of electrical conductivity. The hardness and corrosion resistance in 3.5%NaCl aqueous solution of specimens are gradually enhanced with the increase of Co addition. By adjusting the amount of Co addition and the aging time, the adjustable range of hardness is 200～266 HV and that of electrical conductivity is 17.40～26.10 MS/m.关键词：Cu-Ni-Si Alloy;Electrical Conductivity;Hardness;Corrosion Resistance
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发布时间：2023-12-18 - 摘要：<正>各种（黑色和有色合金）特种铸造方法、各种有色合金（包括新能源材料、高熵合金、金属玻璃等）及复合材料的理论、工艺、设备、测试与控制、计算机应用等方面的科技成果、生产技术和现场经验,以及上述内容的国内外发展动向、行业活动、学术会议消息等。
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发布时间：2023-12-18
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