最新刊期
卷 41 ， 期 6 ， 2021
- 摘要：<正>时间:2021年8月3-6日地点:南昌·嘉莱特精典国际酒店1.会议主办单位中国机械工程学会铸造分会《特种铸造及有色合金》杂志社（武汉）南昌航空大学2.会议承办单位《特种铸造及有色合金》杂志社（武汉）3.会议协办单位广州和德轻量化成型技术有限公司南昌大学中铸产业网4.会议支持单位fsc跨国铸造采购平台广州树森耐火制品有限公司5.会议时间2021年8月3-6日6.会议地点南昌嘉莱特精典国际酒店
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发布时间：2023-12-18 - 摘要：The evolution of microstructures and mechanical properties of Al-Mg-Si-Mn-Cu-Fe alloys with different Mn contents during the homogenization heat treatment were investigated by SEM and in-situ TEM. Nucleation, growth and coarsening of α-Al（FeMn）Si dispersoids were thus quantitatively described. The peak shaped evolution law that dispersoid size is increased gradually and its volume fraction is increased firstly and then decreased during the homogenization heat treatment were measured with high precision, based on ultra-low penetration depth imaging and statistical analysis using low voltage and high resolution. The drastic influence of dispersoids on mechanical properties of alloys was clarified.The results indicate that homogenization heat treatment at 580 ℃ for about 8 h generates the highest volume fraction of dispersoids with adequate size and thus the alloy exhibits optimal comprehensive mechanical properties, while longer treatment leads to coarsening of dispersoids and degradation of mechanical properties. Moreover, the tensile strength and elongation of the alloy can be significantly improved by adding appropriate amount of Mn（0.5%） with homogenization treatment, however, excessive addition of Mn（0.8%） results in serious coarsening of the primary phase, degrading the mechanical properties of the alloy.关键词：Al-Mg-Si Alloy;α-Al（FeMn）Si Dispersoids;Mechanical Properties
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发布时间：2023-12-18 - 摘要：Microstructure, mechanical and corrosion properties of as-extruded Mg-7 Sn-5 Zn-3 Al alloy modified by sliding friction treatment（SFT） were investigated. After SFT, the grain in the surface layer of the alloy is significantly refined and the volume fraction of second phase is remarkly reduced with its dispersed distribution. Tensile testing results indicate that the SFT exhibits excellent mechanical properties, whose yield strength, ultimate tensile strength and elongation are 181 MPa, 366 MPa and 18.1%, respectively. The corrosion resistance of SFT alloy is significantly improved, presenting a low average corrosion rate（4.51 mm/a） and corrosion current density（197.2 μA/cm2）, which is mainly related to the grain refinement, small amount of the second phase and dispersed distribution.关键词：As-extruded Mg-Sn-Zn-Al Alloy;Slide Friction Treatment;Microstructure;Mechanical Properties;Corrosion Behavior
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发布时间：2023-12-18 - 摘要：The thermodynamic model and corresponding Gibbs free energy expression of molten core corium U-Zr-Fe-O system were built up, and thermodynamic data was also established. The thermodynamic properties of million kilowatt PWR core corium was calculated, and the calculated phase diagram, phase fraction and phase composition were presented. The results indicate that with heating up from 2000 ℃, the corium passes through solid-single liquid phases coexistence, solid-double liquid phases coexistence, double liquid phases coexistence, gas-double liquid phases coexistence, and single gas phases. In the range of 2 500～2 950 ℃, it was a typical liquid phase separation zone, and liquid phase 1# is mainly rich in Fe, U, and Zr containing a certain amount of UO2. Liquid phase 2# is mainly rich in UO2, ZrO2, U and Zr containing a very small amount of Fe.关键词：Reactor Core Corium;Thermodynamic Properties;Calculated Phase Diagram;Liquid Separation
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发布时间：2023-12-18 - 摘要：The effects of time, temperature, concentration and liquid-solid ratio on the removal of nitrogen from Al ash were investigated by direct hydrolysis, sodium carbonate hydrolysis and sodium hydroxide hydrolysis. The results indicate that with the increase of temperature, time and liquid-solid ratio, the rate of nitrogen removal by hydrolysis is increased from 0.5% to 36.9% in deionized water. In sodium carbonate solution, the rate of nitrogen removal by hydrolysis of Al ash is increased with the increase of temperature, time, concentration and liquid-solid ratio. Moreover, NaOH promote the hydrolysis process of secondary aluminum ash obviously. The denitrification rule is the same as that of sodium carbonate solution, while the denitrification rate is significantly higher.关键词：Aluminum Ash;Hydrolysis;Solvent;Denitrogenation
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发布时间：2023-12-18 -
Effects of Heat Treatment on Microstructure and Properties of Squeezed Casting SiCp/ZL101 Composites
摘要：3% micron-sized SiCp/ZL101 semi-solid billet was prepared by semi-solid mechanical stirring and near liquidus method, and SiCp/ZL101 composites were obtained by remelting and extrusion. The effects of solid solution and aging on the microstructure and properties of the composite were investigated. The results indicate that the microstructure of SiCp/ZL101 composites is characterized by near spherical α-Al, elongated eutectic Si and polygonal SiC particles. After solid solution treatment, the eutectic Si is converted to nearly spherical one. After further aging treatment, the amount of precipitated phase is increased at the interface between the matrix and the second phase, and the tensile strength, yield strength, elongation and hardness of the composites reach up to 320 MPa, 244 MPa, 6.91% and 114 HV, respectively. The fracture morphology is transformed from microvoid accumulation fracture to quasi-cleavage fracture.关键词：Squeezed Casting;SiCp/ZL101 Composites;Microstructure;Properties- 2
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发布时间：2023-12-18 - 摘要：Assisted with the surface coating of the mixed slurry of silica sol carrying SiC reinforcement, the SiC+SiO2sol-Al composite sheet was fabricated by laminating hot rolling, and microstructure and mechanical properties of the composites were investigated.The results indicate that the interface in SiC+SiO2sol-Al composite sheet is well bonded and the surface is covered with a certain amount of SiO2 and a small amount of Al2O3. The introduced SiC particles are intermittently and evenly distributed in the interlayer of the aluminum foil substrate, which is conducive to interfacial load transfer and makes the grain size of the aluminum foil in SiC+SiO2sol-Al composite sheet more refine and uniform.The fracture mechanism is characterized by ductile fracture and delamination tearing of single-phase aluminum foil substrate layer.Compared with the pure-Al laminated plate, the tensile strength of the composite is increased and the elongation is decreased关键词：SiC/Al Laminated Composite;Surface Treatment;Laminated Hot Rolling;Microstructure;Mechanical Properties
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发布时间：2023-12-18 - 摘要：The superficial composites on Cr-Al2O3 p/65 steel matrix was manufactured by adding the activating element Cr into the Al2O3 perform using squeeze casting. The effects of Cr element on the microstructure and properties of the composites were investigated. The results reveal that the hardness and three-point bending strength of the composites reach 50.7 HRC and 669.5 MPa with adding Cr powder, which are increased by 95.6% and 13.7%, respectively, compared to those of ones without Cr addition. The wetting angle is decreased from 125° to 109° compared to that of ones without Cr powder addition. The microstructure analysis demonstrates that the Fe-Cr phase is generated by added Cr powder with the steel near the Al2O3 particles, indicating a mutual diffusion between the components. The interfacial bonding mode remains mechanical mode. Fracture scanning analysis indicates that the fracture is dominated by brittle fracture, however, the interfacial bonding between the particles and the matrix is well integrated, thus the interfacial bonding properties are greatly improved. In conclusion, the addition of Cr powder can enhance the mechanical properties and interfacial bonding of the composites in the squeeze casting Al2O3 p/65 steel matrix composites.关键词：Al2O3 Ceramic Particles;Steel Matrix Composites;Squeeze Casting;Cr-activated Elements;Three-point Bending Strength
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发布时间：2023-12-18 - 摘要：In-situ TiB2/A356 composites were synthesized by the molten salt reaction method, and the influence of different reinforcement contents on the structure and properties of TiB2/A356 composites were investigated. The results indicate that the grain size of the composites is gradually decreased with the increasing content of TiB2 particles. The strength is increased with the increasing content of the reinforcement, while the elongation is gradually decreased.The yield strength of the composite was predicted by the improved shear-hysteresis model, indicating that the calculated yield strength variation can be well fitted with the experimental values of the TiB2/A356 composites.关键词：In-situ Synthesis;Aluminum Matrix Composites;Microstructure;Mechanical Properties
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发布时间：2023-12-18 - 摘要：The defects such as pores and hot cracks forming in high-strength aluminum alloys during the selective laser melting process were described. The methods to control the formation of defects in the latest researches were summarized, such as reasonable control of process parameters and addition of heterogeneous nucleating agents. The application of the Scheil and phase equilibrium modules, belonging to the phase diagram thermodynamic calculation, in the design and preparation of high-strength aluminum alloy by selected laser melting was introduced. A new method using phase diagram thermodynamic calculation to optimize the alloy composition and promote the rapid nucleation of α-AlFeMnSi was presented, which can realize the quick design of high-strength aluminum alloy without cracks by selected laser melting.关键词：Aluminum Alloy;Selective Laser Melting;Defects;Thermodynamic Calculation of Phase Diagram;Hot Cracks
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发布时间：2023-12-18 - 摘要：Due to the excellent mechanical properties, Mg-Gd（Y） alloys have become important object of research and development. Its high mechanical properties are derived from precipitation strengthen. In recent years, the structure and morphology of precipitation in Mg-Gd/Y alloys have been investigated widely. The understanding of systematic characters of precipitation phase including structure and morphology in Mg-Gd（Y） alloys was increased, and the relationship between precipitation and mechanical properties could be easily mapped, providing a reference for developing high strength magnesium alloys.关键词：Mg-Gd Alloy;Mg-Y Alloy;Precipitation;Structure;Morphology
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发布时间：2023-12-18 - 摘要：As a reinforcing phase and tough phase of metal materials, boron can improve the properties of copper alloys. The role of trace boron in copper alloys and its influence on the properties of copper alloys were expounded. The results indicate that the addition of trace boron（0.15%） can refine the structure, improving the tensile strength and elongation, and also affecting the electrical conductivity and corrosion resistance of copper alloys.关键词：Copper Alloy;Boron;Refinement;Corrosion Resistance
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发布时间：2023-12-18 - 摘要：<正>近年来,中国新能源汽车行业发展迅速,在国家政策的支持下,新能源汽车市场逐步壮大,未来将成为大势所趋。从2020年中国新能源汽车用户反馈的数据来看,普遍存在电池续航能力差的问题亟待改进。针对此问题,目前车身减重是除电池技术升级外的有效增程手段。近年来,铝合金作为轻量化材料在新能源汽车上得到了较好的应用。针对动力电池芯壳材料,西南铝前期开发了280MPa级5xxx铝合金板材产品,有效解决了动力电池
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发布时间：2023-12-18 - 摘要：<正>据悉,作为我国使用铝基复合材料占比大的航天器,中科院金属研究所提供的铝基复合材料,加工出几百件不同类型的部件用于"天问一号"火星车。由于长距离飞行与顺利入轨并着陆的要求,火星车的材料首先要求是‘轻’,其质量控制甚至以g为单位;其次要求它‘强’,以满足承载和耐磨的需求;同时还要‘韧’,能满足火星车在未知的火星表面‘服役’面临的冲击、碰撞等复杂工况而不破坏。但传统的金属材料很难兼顾到火星车的
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发布时间：2023-12-18 - 摘要：<正>步入21世纪,铸造当代大学生的核心竞争力已经逐步成为现代化教育教学的最终目标之一,其是保证大学生个人能力,并使当代大学生不断进步和发展的不竭动力。具体而言,大学生核心竞争力主要指能为当代大学生提供比较竞争优势的能力,其包括知识资源传授、知识信息配置以及知识框架整合等多方面内容。充分发现并培养当代大学生的核心竞争力能使他们成为坚实的共产主义接班人,继而学习、践行、继承、发展社会主义核心思想,将我国建设成为富强、民主、文明、和谐、美丽的社会主义现代化强国。简而言之,在科学技术迅速发展的当代社会,大学生核心竞争力的培养与铸造决定了整个国家及社会未来的发展方向与进步速度。在充分、全面、系统性地铸造当代大学生的核心竞争力
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发布时间：2023-12-18 - 摘要：<正>《思想政治教育方法论》一书是由郑永廷联合高等教育出版社出版的图书。《思想政治教育方法论》一书是基于马克思列宁主义、毛泽东思想等中国社会理论体系构建的理论性丛书,本书根据当代社会的基本发展、人的全面发展等方面,遵循了统一的原则,对思想政治教育进行了高度概括,同时继续发展了思想政治教育、理论、功能以及历史发展等。本书定位于指导思想政治教育的工作方法、认识方法、反馈评估方法等,适用人群为党群工作者以及相关从业人员,是一本具有科学指导性、时代价值
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发布时间：2023-12-18 - 摘要：<正>中国的青铜器作为商周时代的经典作品,以其自身精美的纹饰和独特造型,体现出一种庄严肃穆的氛围,被人们视为权势的象征。因其在中国古代铸造史上浓墨重彩的地位,也成为了中国古代文化的象征和标志。蕴含的商周礼教文化也激发了人们对其浓厚的研究兴趣。礼器是作为贵族举行丧葬、祭祀、出征等多种重要活动时的重要用品,其铸造工艺纯熟,历史悠久,多数体现在了礼器铸造上。礼器的铸造需要大量优秀的铸造工匠和优秀的铸造技艺,多被统治阶级集中在大城市专为王公贵族服务。随着礼器铸造技术的成熟,铸造礼器可以包括全方位的用品,除了祭祀用的炉、鼎等,还包括宴席上为了
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发布时间：2023-12-18 - 摘要：<正>《铝合金锻造生产》一书,是中南大学出版社2011年出版的《中国有色金属丛书》之一。本书通过对铝合金锻造的基本原理、工艺流程、技术性能、加工方法的系统论述,让读者在系统了解铝合金锻造生产的基本原理基础上,对其适用领域、工艺技术优缺点,核心关键技术、以及工艺对环境的影响和治理有了更深入、全面地了解,同时也就目前世界范围内的铝合金锻造生产工艺技术的全球化发展和科技前景做了介绍,帮助学习者以更广阔的视角去学习,是目前我国有关有色金属工业化生产应用
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发布时间：2023-12-18 - 摘要：<正>《深度营销:解决方案式销售行动指南》（王鉴编著,机械工业出版社,2017年2月）一书是铸造工业润滑油营销渠道理论研究与实践探究方面的专业著作,该书对铸造工业润滑油产品营销的客户获取、市场开拓、渠道打通进行了详细的介绍,适用于市场营销相关专业教学实践,并对铸造工业润滑油营销渠道对接、优化与创新也具有重要的价值和作用。该书综述了同质化产品市场竞争背景下客户需求的精准定位,对市场营销中产品的定价、包装、推广、宣传也进行了详细介绍,并对市场营销过程中产品给予用户的差异化体验做了重点分析,以有效满足用户的个性化需求为导向,通过产品和服务带给用户良好的营销
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发布时间：2023-12-18 - 摘要：<正>熔模铸造为近净成型的一种技术,用于铸造以及成形具有更复杂或特殊形状的零件。很多熔模铸件都是典型的各种空间曲线零件,广泛应用在电力、机械等设备中、这些设备具有恶劣的工作环境,对工作性能提出较高的要求。传统铸造的浇注系统设计、轮廓设计、结构设计以及制定注蜡工艺的参数等都是根据经验以及试验来确定,主要基于技术人员在实际工作中积累的经验,缺乏科学依据,需要对结构、铸造工艺计划进行反复修改,以实现预期的技术要求,尤其是对于复杂或关键零件。这种试验与方法结合的处理方法,会导致较长的开发周期、较高的铸
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发布时间：2023-12-18 - 摘要：<正>铸造是装备制造业发展的核心支撑。随着装备制造业的迅猛发展,铸造企业在庞大的市场需求下获得了极好的产业发展空间。根据2021年中国铸造协会发布的《铸造行业"十四五"发展规划》所示,我国年铸件总产量已经连续21年成为世界上产量最高的国家。后疫情时代,全球经济增长速度均受到了明显的阻力,全球经济发展环境并不容乐观,铸造企业也正面临着较大的市场压力。持续发展低碳经济,贯彻十四五"碳达峰、碳中和"的整体发展战略下,铸造企业正面临着更深层次的产业结构调整。一、低碳经济环境下铸造企业发展面临的困境铸造工艺决定了铸造企业对于生态资源消耗巨大,尽管
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发布时间：2023-12-18 -
- 摘要：Mg-4 Zn-xY alloys with different yttrium（Y） contents were prepared by high energy ball milling and vacuum hot pressing sintering. X-ray Diffraction（XRD）, optical microscope（OM） and scanning electron microscope（SEM） were used to observe and analyze the composition of the alloy and corrosion products. Through potentiodynamic polarization and immersion corrosion experiments, the corrosion properties and corrosion mechanism of the alloy were analyzed. The results indicate that with the addition of Y, the formation of new second phases(Mg12YZn, Mg24Y5) can be observed. After potentiodynamic polarization, passivation occurs in Mg-4 Zn-xY alloy and effective Mg（OH） 2 passivation film is generated. The addition of the Y element contributes to uniform distribution of the alloy structure and refinement of the grains, leading to the network distribution of the second phase, promoting passivation and acting as a corrosion barrier layer, and effectively improving the corrosion resistance of the alloy. Mg-4 Zn-10 Y alloy has low corrosion current density, low corrosion rate and good corrosion resistance due to its relatively uniform and fine microstructure.关键词：Mechanical Alloying;Mg-Zn-Y Alloy;Microstructure;Corrosion Resistance
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发布时间：2023-12-18 - 摘要：The effects of different Sc contents on microstructure and mechanical properties of Zl101 alloy were investigated by OM, SEM and TEM. The results reveal that when the Sc content is 0.3%, the grain size of α-Al can be refined and the morphology of eutectic silicon can be improved. Meanwhile, the Rockwell hardness（HRC）, tensile strength and elongation of the alloy reach maximum values of 29, 197.95 MPa and 11.06%. After adding Sc in ZL101 alloy, Al3Sc phase can be generated to act as heterogeneous nuclei to refine grain size remarkably.关键词：Sc;ZL101 Alloy;Microstructure;Mechanical Properties
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发布时间：2023-12-18 - 摘要：The effects of different heating-aging process at initial temperature of 100 ℃ on hardness, conductivity, room temperature tensile properties and microstructure of 7050 aluminum alloy were investigated. The results indicate that the average size and size range of precipitates are increased continuously with the increase of the final aging temperature at the heating rate of 20 ℃/h, which is larger than that at 40 ℃/h when the final aging temperature is 200 ℃. The hardness and room temperature tensile properties of the 7050 aluminum alloy are firstly increased and then decreased with the increase of precipitate size, and the fracture is characterized by mixture of intergranular and transgranular fracture. Meanwhile the conductivity is increased with the heating-aging process. The 7050 aluminum alloy with excellent strength and corrosion resistance can be obtained by adjusting the heating rate and final aging temperature, which requires short aging time.关键词：7050 Aluminum Alloy;Heating-aging;Conductivity;Mechanical Properties
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发布时间：2023-12-18 - 摘要：The effects of structural parameters on the mechanical behavior and energy absorption properties of investment casting lattice Al were investigated. The pyramid-shaped 3 D lattice Al was fabricated through the combination of computer-aided design, sterolithography apparatus and investment casting technology. The quasi-static compression mechanical behavior of the lattice Al were characterized and the mechanical properties of the lattice show obvious dependence on the structural parameters. When the inclination angle is 60°, the relative density, flow stress and energy absorption per unit volume are increased by 21%, 142% and 159%, respectively, where the plateau stress is around 15 MPa and the energy absorption per unit volume is 2.7 MJ/m3, which are increased to around 22 MPa and 10.6 MJ/m3 with the angle increasing to 65°, respectively. The pyramid-shaped 3 D lattice Al is similar to common porous metals, where compression stress is closely related to the structural parameters of the material and has obvious elastic zone, platform zone and densification zone.关键词：Casting;Lattice Al;Length-diameter Ratio;Stress-Strain Behavior;Energy Absorption
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发布时间：2023-12-18 - 摘要：In order to enhance the room-temperature strength of a casting CrCoNi medium-entropy alloy, 3% Mo and 0.5% C were added into the alloy. The carbide precipitation behavior and its effects on phase structure, microstructure, hardness and compressive properties at room temperature of the CrCoNi alloy were investigated. Traditional processes including arc melting, drop-casting, solid solution treatment at 1 250 ℃ for 6 h and aging at 950 ℃ for 1 h were adopted. The dispersed carbides are precipitated from the alloy after aging. Fine carbides are evenly distributed in the intragranular regions, and coarse carbides are distributed on the grain boundaries. The hardness of the（CrCoNi）96.5Mo3C0.5 alloy is increased from 157 HV of the CrCoNi alloy to 250 HV, and the yield strength at room temperature is increased from 223 MPa to 342 MPa, which is attributed to the precipitation strengthening of carbide.关键词：Medium-entropy Alloy;Carbide;Microstructure;Hardness;Compressive Property
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发布时间：2023-12-18 - 摘要：The drawing processing parameters of two-joint roller dies for aluminum alloy wires with different compositions were investigated. The spreading characteristics of aluminum wire was tested. The results indicate that the aluminum billet presents inverse tension, leading to the characteristics of tiny spreading, which varies obviously with the strength of the aluminum alloy. The difference of drawing force between drawing die and two-joint roller die was investigated on the tensile testing machine. The results reveal that drawing force of roll die is decreased by more than 28%, showing huge potential of saving energy. The structure of the roll die was modified, and the same section reduction rate as the drawing die was adopted to draw the aluminum wire with different compositions on the same water tank drawing machine.The drawing break line, current, and drawing oil of the two dies were compared systematically. The results demonstrate that aluminum alloy wires with different compositions can be continuously drawn by combination of roller dies, irrespective of the working hardening, which exhibits advantages of energy saving, easy assembling, environmental protection and low wear.关键词：Core Design;Aluminum Wire Spreading Characteristics;Drawing Force
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发布时间：2023-12-18 - 摘要：A numerical simulation on the directional solidification process of high purity aluminum was conducted by finite element simulation software ProCAST. The directional solidification was successfully simulated by self-built model. The result reveal that during the solidification process, the special flow field and temperature field lead to the formation of the abnormal solute enrichment zone in the ingot, which should be eliminated through appropriate stirring in the middle of solidification during the actual production.关键词：High Purity Aluminum;Directional Solidification;Numerical Simulation
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发布时间：2023-12-18 - 摘要：Based on the ABAQUS software, drawing process of the TC4 titanium alloy with ?0.5 mm filament was simulated. The results indicate that along the workpiece axis, the residual stress is greater in the contact area between the workpiece and the mold compression cone, while along the workpiece radial direction, distribution area of the minimum residual stress varies with the mold compression angle. As the compression rate increases, the distribution area of maximum residual stress outside the workpiece is increased. When the compression rate is greater than 50%, the workpiece is cracked. The drawing temperature is increased with increase of mold compression angle and compression ratio. In actual production, it is more suitable for the pass compression rate less than 20%, the total compression rate less than 50%, and the mold compression angle less than 25°.关键词：TC4 Titanium Alloy Simulation;Die Compression Angle;Compression Ratio;Residual Stress;Drawing Temperature
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发布时间：2023-12-18 -
Microstructure of Squeeze Castings at Different Position with Wall Thickness and Solute Distribution
摘要：The microstructure and Cu content of the squeezing casting components in different positions and the influence of wall thickness on the microstructure of the specimen and Cu content was analyzed by optical microscope and spectrometer to observe and measure microstructure and solute content changes in the various parts. The results reveal that the grain size becomes coarse with the increase of distance of ingate distance（158, 201, 245 and 284 mm） which is changed from 18.35 μm to 39.85 μm. The content of Cu is increased from 1.73%～1.77% in the surface to 1.81%～1.87% at the center, and the hardness（HV） is decreased from 102.5～106 at the surface into 96～99 at the center. With increasing in wall thickness（6, 17, 27.5 mm）, the central hardness value is decreased to 96 HV, and the grains become coarse to 45.22 μm accompanied with the increasing Cu content. From the surface to the center, the copper content is increased by 1.73%～1.75 to 1.83%～1.85%, and the hardness is decreased.关键词：Squeeze Casting;Different Position;Wall Thickness;Cu Content;Hardness- 2
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发布时间：2023-12-18 - 摘要：A thixotropic-core compound forging technology was proposed for forming an aluminum-steel bimetal standard cylinder spur gear. The effects of initial temperature and thickness of the steel shell on bimetal synchronous deformation mechanism of the gear were investigated by finite element method（FEM）. The results indicate that the synchronous deformation behavior of the billets is determined by the ratio of thickness to radius of the steel shell. During the forming process, reliable mechanical interlock is formed between the aluminum alloy core and steel shell. In the bimetal gear, the thickness at the tooth tips of steel layer is increased and that at tooth roots is decreased, thus forming cracking dangerous zone. It is helpful to improve the fluidity of steel shell with increasing steel shell temperature. However, the aluminum core suffers anoverly heating when contacting steel layer at higher temperature, leading to the sharply decrease of the flow stress and disorders. When the initial thickness and temperature of steel shell were 4 mm and 1 100 ℃, respectively, the synchronous deformation quality is desirable. In conclusion, the forming dies were designed and the experiment was carried out based on the simulated analysis. A well-formed bimetal gear was obtained, demonstrating that the thixotropic-core compound forging technology was a satisfactory method for producing complex aluminum-steel bimetal components.关键词：Thixoforming;Compound Forging;Bimetal Component;Light Weight
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发布时间：2023-12-18 -
Phase-field Simulation on Tilted Dendrite Growth of Ti-4.5Al Alloy during Directional Solidification
摘要：Based on the Karma thin interface continuous phase-field model, tilted dendrite growth patterns of Ti-4.5 Al alloy during directional solidification was simulated by the freezing temperature approximation, and the three-dimensional dendrite growth morphologies at tilt angles of 0°, 15°, 20°, 30° and 45° were observed. The results indicate that the asymmetry of the dendrites is enhanced, and the morphologies of the secondary and tertiary dendrites become coarse with the tilt angle increase. In addition, the higher the temperature gradient is, the greater the solidification driving force is, where the secondary and tertiary dendrites are more and coarser, and small protrusions that grow along the direction of the temperature gradient are generated at the tip of the tertiary dendrite. The tip position of the tilted dendrite is lower than the normal one along the tilted X-axis direction, thus the tilted dendrite is easier to be eliminated from growing competition together with normal ones, which is consistent with the results observed in the experiment.关键词：Ti-4.5Al Alloy;Directional Solidification;Tilted Dendrite;Phase-field Simulation- 2
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发布时间：2023-12-18 - 摘要：From aspects of product structure, material composition, mould structure and processing measures, origination of crack in squeezing casting ADC12 aluminum alloy end cover was analyzed. Aiming at the crack defects, the preventing measures were provided, and the satisfied effects were obtained through increasing feeding pressure, decreasing holding time and quenching in water.关键词：ADC12 Alloy;Squeezing Casting;Crack
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发布时间：2023-12-18 - 摘要：The problem of impact during the mold opening and closing was analyzed due to the low expansion ratio under 25 000 kN clamping force, and optimization design on the hinge system was carried out. Firstly the mechanical model of the clamping mechanism was built up and the stress and displacement were calculated using finite element method in order to validate the stiffness and strength of each component. A rigid-flexible combination multi-body dynamic model of the hinge system was set based on the parameter of elbow stiffness. Finally the optimized design was built up upon the multi-body dynamic model using elbow hinge coordinates as design variables. As the results of comparison with the origins, the optimized design has enlarged the expansion ratio from 21.45 to 24.57, and the stroke is increased from 1.03 to 1.08. The impact during mold opening and closing of the optimized design is decreased greatly.关键词：Die Casting Machine;Hinge System;Finite Element Analysis;Multibody Dynamic;Optimization Design
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发布时间：2023-12-18 - 摘要：Dimensional deviation of fillet is an important factor in wax mold preparation, shell preparation and casting solidification in investment casting, which affects the dimensional accuracy of castings. A fillet model with 5 inner chamfers and 1 outer chamfer was designed, and KC3898 NRR wax was used to fill the wax mold and prepareceramic shells.The K423, K424, K438 superalloy castings were poured, and Geomagic Control software was conducted for deviation analysis of fillet radius dimension. The deviation of the fillet radius dimension during the preparation of wax molds is in range of 3% to 30%, and the thermal expansion correction range of the ceramic shell is 2%～8%. Among the three alloys, castings poured by K438 superalloy exhibit the smallest fillet radius dimension deviation.关键词：Investment Casting;Fillet Radius;Superalloy;Dimensional Deviation
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发布时间：2023-12-18 - 摘要：Excavator sleeves with austempered ductile iron were prepared by centrifugal casting process combined with isothermal quenching in order to improve the service life. Microstructure, mechanical properties and wear resistance of the samples were analyzed. The results indicating that the quenching microstructure of ADI is fine, composed of ultrafine needle-shaped ferrites, spheroidal graphite and residual austenite. Under dry and oil friction conditions, the friction coefficient and wear loss of ADI are far lower than that of 45 steel. ADI meets the performance requirements of excavator sleeve, showing a good application prospect in construction machinery.关键词：ADI;Self-lubrication;Wear Resistance;Excavator Sleeves;Centrifugal Casting
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发布时间：2023-12-18 - 摘要：<正>2021年"第27届中国铸造协会消失模V法实型分会"年会,根据疫情形势预期于2021年7月～8月举办。为做好消失模V法实型铸造分会年会交流内容的组织工作,营造良好学术氛围,推动消失模铸造行业创新、协调、绿色、开放、共享发展,促进行业单位之间交流与合作,展示自身在技术研发、管理创新、生产实践方面等取得成果,现公开广泛征集年会论文。一、征文内容（所有铸造相关技术）1.消失模、V法、实型铸造的基本理论、基本
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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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