最新刊期
卷 42 ， 期 5 ， 2022
- 摘要：<正>1、会议主办单位中国机械工程学会铸造分会中国兵工学会材料科学与技术专业委员会中国机械工程学会塑性工程分会《特种铸造及有色合金》杂志社（武汉）2、会议承办单位《特种铸造及有色合金》杂志社（武汉）3、会议地点待定4、会议时间2022年秋季（11月前后,具体时间待定）5、征文内容与压铸（包含高真空压铸,局部加压）、低压铸造、挤压铸造、差压铸造、半固态加工相关的论文（含生产技术、企业管理、产业分析、市场动态、营销策略、发展展望等）皆可应征。主要包括:①铝、镁、钛、锌、铜等合金及复合材料的组织,性能和应用;②压铸、低压铸造、挤压铸造、
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发布时间：2024-04-01 - 摘要：The centrifugal casting process of super cylinder liner was modeled in segments using ProCAST software, and the temperature field, flow field and pressure field of the casting were coupling calculated. The results indicate that the metal liquid fills the mold in the form of laminar flow, and the filling time is 90.3 s. The castings are solidified from the outside to the inside layer by layer, and the final solidification is located in the middle of the thick wall end of the casting. The pressure field is concentric distribution, and the size is related to the diameter of the inner hole of the mold, the wall thickness of the casting and the centrifugal speed. The changes of fields above are mainly induced by the centrifugal force, the gravity of the metal liquid, and the strong cooling coupling of the cylinder liner mold.关键词：Super High Molybdemum Cast Iron Cylinder Liner;Centrifugal Casting;Numerical Simulation
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发布时间：2024-04-01 - 摘要：Several low-cost Ti-Al-V-Fe alloys with different composition were designed, and uniform（α+β） titanium alloy ingots were obtained by thenon-consumable vacuum arc melting and heat treatment. The microstructure and mechanical properties of low-cost titanium alloys with different Fe and V contents were investigated by means of scanning electron microscope, test machine and digital micro-hardness tester. The results indicate that absence of difference between the microstructure of titanium alloy with different composition can be observed, which are coarse columnar crystals composed of Widmannstatten and basket-net structure. With the increase of Fe and V, the yield strength and tensile strength of the alloy are also increased, where the strengthening effect of Fe is more significant than V. As Fe content increases, the reduction of elongation is increased obviously, and the higher Fe content leads to the larger lattice distortion, resulting in phase embrittlement. V can refine the microstructure of the titanium alloy, and the elongation of the titanium alloy is increased slightly as V content increases.关键词：Low-cost Titanium Alloys;Ti-Al-V-Fe;Microstructure;Mechanical Properties
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发布时间：2024-04-01 - 摘要：近日，上海交通大学轻合金精密成型国家工程研究中心吴国华教授团队与澳大利亚昆士兰大学的David H.StJohn教授团队合作，在镁稀土合金晶粒细化方面的研究取得重要进展。镁稀土合金密度低、比强度和比刚度高、耐热性能好、阻尼减振性优良，在航空航天和交通运输等领域具有广阔的应用前景。
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发布时间：2024-04-01 - 摘要：近日，青海省科技厅组织专家对中国科学院青海盐湖研究所承担的科技合作专项“氢氧化镁/石墨烯复合功能材料的制备及在聚丙烯中的应用研究”进行了验收。该项目采用水热法制备氢氧化镁/石墨烯（MDH/GO）纳米材料，研究了该纳米阻燃剂的生长机理，以及用于改性的氢氧化镁/石墨烯（MDH/GO）纳米结构和组成比例；以工业级KH-550改性剂和P204为原料，开展了合成新型功能性表面改性剂的研究，
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发布时间：2024-04-01 - 摘要：来自中金研究消息，受地缘政治局势影响，近期欧洲现货电价在淡季再度冲高至300美元/兆瓦以上，预计欧洲铝厂已经关闭的产能在今年复产的概率较低。此外，随着欧洲未停产的铝厂与当地政府电力合约到期，新合约价格较高也可能促使电解铝企业减产。2022年，预计国内和海外电解铝产量将分别同比增长3.9%和2.1%，总产量增速下调为3.1%。全球铝供需缺口从2021年的112万吨扩大至163万吨。
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发布时间：2024-04-01 - 摘要：德国《商报》报道，现代化的特斯拉汽车工厂在柏林格林海德启动。特斯拉柏林工厂的压铸车间，采用特斯拉“公司色”的巨型压铸机正在生产车身部件，该压铸机的模具重达50t。该压铸车间不久还将压制电池箱，即4680锂电池的壳体。据介绍，柏林工厂里将再加装六台“超级压铸机”，总计将达8台。是因为Model Y车型不仅后车身一体压铸成型，而且前车身也将由单次压铸制成。这款跨界车将变成了由极少部件组装而成的一个结构套件。
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发布时间：2024-04-01 - 摘要：近日，中国汽车工业协会（“中汽协”）举行汽车工业经济运行信息发布会。中汽协表示，今年一季度，汽车产销同比略有增长，增速比上年同期明显回落。但在细分车型方面，新能源汽车产销延续了快速增长势头，产销双双超过百万辆，市场占有率达到了19.3%，新能源汽车战略引领作用进一步凸显。发布会报告显示，3月，汽车产销分别完成224.1万辆和223.4万辆，环比分别增长23.4%和28.4%，同比分别下降9.1%和11.7%。其中，3月，乘用车产销分别完成188.1万辆和186.4万辆，同比分别下降0.1%和0.6%；
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发布时间：2024-04-01 - 摘要：随着大学教育理念不断发展,大学专业的不断增加,就业问题愈发严峻,大学生所面临的就业问题日益突出,在这种教育规模扩大的背景下,自主创业逐渐成为大学生发展规划新宠,而针对大学生自主创业所设置的专业创业教育,就是不断开发创新意识,发展创业思维。我国已经开始重视创业教育,并有典型案例存在,将对大学生创业教育的情况以及开设专业创业教育对大学生发展的影响进行分析。在国外,很多大学生对于创业很热衷,创业的意识已经深植于脑海之中,读大学的过程中,就已经在积极思考自身创业规划,在读书的同时积极地参与各种经济活动,
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发布时间：2024-04-01 - 摘要：随着近年来我国铸造产业快速发展,铸造产品工艺技术也得到全面进步,各种各样具有中国特色的铸造产品出口到世界各个国家,这也就给我国高校铸造专业美术教育提出了新的要求。要逐步将青铜器艺术性融入当代铸造专业美术教育中,加深铸造专业学生对青铜器艺术文化的认知与理解。铸造专业美术教育事关我国铸造工艺发展水平、专业人才培养与铸造产品美学价值,故此,依靠何种策略、何种方式、何种路径强化铸造专业教育青铜器艺术性研究尤为迫切。一方面,青铜器艺术是我国传统艺术体系的重要组成部分,
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发布时间：2024-04-01 - 摘要：随着近年来我国经济体制改革逐步深化,我国铸造产品出口到全球众多国家,这也就给我国铸造企业发展带来了全新的机会。高校如何针对铸造专业学生更有效开展创新创业教育,针对学生的个性化创新需求、铸造行业未来发展需求、专业学科设置特点构建系统科学的创新创业教育模式就成为当前需要解决的问题。随着我国铸造企业向着智能化、数字化、国际化方向快速发展,铸造专业学生创新创业教育模式对铸造行业人才培养具有什么样的意义、对铸造行业发展具有什么样的作用、
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发布时间：2024-04-01 - 摘要：随着近年来人们对铸造工艺品艺术审美需求的提升,我国铸造产品工艺水平快速提升,如何应用青铜器纹样绘画提升铸造工艺产品美学设计水平,已成为铸造产品设计者研究的重点课题。铸造产品是否具备较高的设计水平、是否具有较高的美学价值、是否符合现代人的艺术审美需求事关我国铸造行业发展水平、铸造工艺技术水平,故此,依靠何种策略、何种方法、何种路径促进青铜器纹样绘画在现代铸造设计中得到广泛应用,提升我国铸造产品艺术设计美感就显得尤为迫切。一方面,青铜器纹样绘画是起源于中国青铜器纹饰艺术的绘画方式,包括饕餮纹、
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发布时间：2024-04-01 - 摘要：近年来,随着我国经济发展水平与科技发展水平的不断攀升,各类建筑、建设、制造的基础需求不断加大,这一方面推动了国内工商业市场的飞速发展,另一方面也对传统行业的现代化升级提出了全新要求。同时,随着经济全球化与全球商业一体化进程的不断加快,现阶段全世界、各地区的文化与技术交流日益密切,而这一趋势不但促进了国内生产技术与科技能力的交互,也为国内市场吸引了一大批极具实力的外资商业与外资企业,进而使国内工、商业市场更加繁荣,并创造了极大的物质与经济财富。
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发布时间：2024-04-01 - 摘要：在我国现阶段的工业社会发展中,锻造行业与锻造相关企业是一类起到重要角色的关键性产业。一方面,锻造行业需要为工业、商业、建筑业等相关产业提供各类的设备支持与技术支持,以保障各行业的高效稳定运营,另一方面,原材料的开发与供给市场也需要根据锻造产业的发展需求及时做出调整,以满足锻造生产的实际需求。在上述发展背景下,得益于我国经济实力与科技发展水平的飞速提升,我国锻造产业与锻造相关企业在近几十年的发展中发生了翻天覆地的变化,这不但体现在技术稳定、质量优良的工业锻造产品之中,也充分展现在锻造行业的自动化与智能化方向。
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发布时间：2024-04-01 - 摘要：近年,随着经济与科技的飞速发展,我国生产水平与生产能力进入到了一个新的发展阶段,这使得国内市场快速繁荣,各类生活与生产产品争相涌现。铸造工艺品是居民日常生活中一类极其常见的应用或装饰物品,小到家居环境中的零碎摆件,大到城市广场中的铸造工艺雕塑,无一不展现了铸造工艺品的精致和精美。在铸造工艺品的展示和销售过程中,工艺品外包装的设计将为购买者留下十分深刻的印象,这也使得铸造工艺品包装设计问题成了一项十分关键的环节。
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发布时间：2024-04-01 - 摘要：图胜文百倍,新闻摄影逐渐兴起,摄影的作品被各种报纸杂志应用,这种图文并茂的模式能够吸引读者注意,让读者对内容更加关注,将读者带入读图时代。读图时代的来临具有明显标志性变化,就是媒体对图片报道的需求爆炸性增长,这种变化并非偶然,是时代更替,生活节奏变化,信息爆炸所带来的必然结果。因此,在企业的宣传工作中,新闻摄影是十分重要的一个载体,新闻摄影能够表达思想,反映真实情况,传递新闻与企业形象。在企业的发展过程中,新闻摄影的价值主要体现在三个方面,
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发布时间：2024-04-01 - 摘要：The microstructure evolution and formation mechanism of rheo-die-casting ADC12 alloy for low superheat inclined plate were investigated by means of metallography, X-ray diffraction and scanning electron microscope, and its mechanical properties were tested. The results show that the microstructure of the alloy is converted from coarse dendrites to spherical or near-spherical grains with the increase of the distance from the pressure chamber. The mechanism of microstructure formation is attributed to dendrite fragmentation and melt explosion nucleation. It is also proved that rheo-die-casting can improve the mechanical properties of the alloy, where the tensile strength reaches 248 MPa and the elongation is slightly better than that of conventional ones.关键词：Rheo-diecasting;ADC12 Aluminum Alloy;Microstructure;Mechanical Properties
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发布时间：2024-04-01 - 摘要：Mg-6 Gd-1 Er-0.5 Zr（GE61 K） alloy with low rare earth content was designed. The alloy sheet was prepared by rapid rolling. The yield strength, tensile strength and elongation of the alloy sheet reach up to 201 MPa、248 MPa and 17.4%, respectively. After annealing tretament, the strength of the sheet is decreased slightly, however the elongation can be increased to 20.7%. Solution strengthening and texture strengthening are the main factors affecting the mechanical properties of the alloy sheet.关键词：Mg-Gd-Er-Zr Alloy;Rapid Rolling;Microstructure;Dynamic Recrystallization;Mechanical Properties
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发布时间：2024-04-01 - 摘要：The prepared Cu-0.2 Be-0.8 Co alloy was treated by 950 ℃×1 h solid solution+different deformation rate of cold deformation+480 ℃×4 h aging treatment, where the cold deformation rate are 10%, 20%, 30%, 40%, 50%, respectively. The hardness and conductivity rate of the alloy after different cold deformation treatments were tested by sclerometer and conductometer. The grain and precipitate characteristics are also observed and analyzed by optical microscopy（OM） and transmission electron microscopy（TEM）. The results indicate that different degrees of cold deformation between solution and aging have a significant effect on the hardness of the alloy, while little effect on the conductivity. Compared with the solution+aging treatment without cold deformation, the hardness and conductivity of the alloy reach 176 HB and 36.714 MS/m, respectively, with 50% cold deformation applied before aging, greatly increasing the hardness by 50.4% on the premise of small sacrificial conductivity. Grains of the alloy undergo different degrees of plastic deformation, where the morphology, dimension and distribution of precipitates are changed significantly, and the interaction with dislocations is increased. The cold deformation exerting reserves energy for subsequent aging precipitation, improving precipitation efficiency and precipitation rate, thus enhancing the hardness of the alloy significantly.关键词：Cu-Be-Co Alloy;Thermo-mechanical Treatment;Hardness;Conductivity;Microstructure
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发布时间：2024-04-01 - 摘要：The bio-based cold box resin was synthesized by a one-step method with rosin, phenol, methanol and paraformaldehyde as raw materials, zinc acetate as a catalyst. The effects of the molar ratio of phenolic aldehyde, the reaction temperature, the amount of catalyst and rosin dosage on the performance of the products were investigated by testing the refractive index, viscosity, accommodation, and intensity of the product. The results indicate that the suitable synthesis conditions for the bio-based cold box resin are presented as follows: the molar ratio of phenol to paraformaldehyde of 1∶1.6, the reaction temperature of 110 ℃, the amount of catalyst of 0.2%, and the addition of rosin of 3%. Through the analysis of infrared, molecular mass distribution, strength and thermogravimetric data, the tensile strength of resin sand with bio-based cold core box resin addition is significantly increased with a proper improvement in thermal stability, gas evolution and breathability.关键词：Bio-based;Cold Box Resin;Synthesis;Property
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发布时间：2024-04-01 - 摘要：Focusing on metal-impregnated carbon materials, the tribological properties and the current-carrying quality of metal-impregnated carbon materials were investigated on the HST-100 current-carrying friction tester under different friction conditions. The results reveal that the velocity has dominant influence on the current-carrying friction properties. When the threshold value of 70 m/s is exceeded, the current-carrying quality and tribological properties of the friction pair materials are significantly reduced, where the average current-carrying efficiency is reduced from 98% to 67.8%, and the average current-carrying stability is reduced by 83%, and the average wear rate is increased by 510%. Microstructure observations show that the proportion of the metal film is decreased and the proportion of the carbon film is increased gradually, so the current-carrying quality and the tribological properties are decreased gradually with the increase of the velocity and the current. In the process of current-carrying friction, the current-carrying quality and tribological properties are interplayed. Following the friction pairs with higher current-carrying quality, the good tribological properties are presented, which is conducive to improving conductivity and reducing wear.关键词：Current-carrying Quality;Tribological Properties;Friction Pair;Conductivity
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发布时间：2024-04-01 - 摘要：Through high temperature compression experiment, the variation of high temperature rheological stress of 7055 high strength aluminum alloy for aerospace was investigated under different temperatures（330, 380, 430 and 480 ℃） and strain rates(0.001, 0.01, 0.1 and 1 s-1). According to the high temperature compression experimental data, with the help of linear regression method, the peak flow stress constitutive equation and steady flow stress constitutive equation of 7055 high strength aluminum alloy were established. The results indicate that at the beginning of hot compression deformation, the flow stress of 7055 high-strength aluminum alloy is increased rapidly to the peak value with the increase of stress, then the true stress is decreased with the increase of stress variable due to strain softening until the steady-state flow stage. When the strain rate is constant, the flow stress is decreased with the increase of deformation temperature. When the deformation temperature is constant, the flow stress is increased with the increase of strain rate. Finally, the hot working diagram with true strain of 0.2 was established. In the region of forming temperature of 330～410 ℃ and strain rate of 0.001～0.05 s-1, the power dissipation coefficient is more than 20%, which is the reasonable process parameters of 7055 high strength aluminum alloy for aerospace.关键词：7055 High Strength Aluminum Alloy;Thermal Deformation Behavior;Constitutive Equation;Hot Working Drawing
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发布时间：2024-04-01 - 摘要：Friction stir processing（FSP） and subsequent solution and artificial aging（T6） treatment were conducted on hypoeutectic and eutectic Al-Si-Mg-Sc alloys, and the microstructure as well as mechanical properties of the alloy were investigated at different states. The results indicate that FSP can eliminate the hole defects and effectively destroy Si phase network structure, breaking intermetallic AlSi2Sc2, Al8Mg3（SiSc）6Fe phases in the casting alloy. T6 treatment can promote the precipitation of high density β″ phase in the FSP alloys. FSP can greatly optimize the mechanical properties of hypoeutectic and eutectic Al-Si-Mg-Sc alloys in T6 state. The strengthening mechanisms of the alloys with FSP and T6 treatment include precipitation strengthening and excess phase strengthening effects, and fracture mode is typical plastic fracture.关键词：Al Alloy;Friction Stir Processing;Microstructure;Mechanical Properties
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发布时间：2024-04-01 - 摘要：The effects of different Si contents and ultrasonic treatment on microstructure and mechanical properties of Al-5 Mg-xSi alloy were investigated by metal mold gravity casting. The results indicate that the shape and distribution of the primary α-Al phase and the reinforced phase Mg2Si in the alloy are also varied with the increase of Si content. After ultrasonic treatment, the main phase composition in microstructure of the alloy with different Si contents has little change, where the α-Al grains become rounder and the distribution of β-Mg2Si is also more uniform. However, the β-Mg2Si agglomeration occurs when the Si content is 2%. The tensile strength and elongation of the alloy are firstly increased and then decreased with the increase of Si content. The as-cast mechanical properties of the alloy presents desirable when the Si content is 1.6%, where the tensile strength and elongation is 141.2 MPa, and 1.5%, respectively. After ultrasonic treatment, the mechanical properties of the alloy are desirable with the same Si content, where the tensile strength and elongation is 168.0 MPa and 2.6%, which are 19% and 73% higher than the as-cast ones, respectively.关键词：Al-Mg-Si Alloy;Si Content;Metal Mold Gravity Casting;Ultrasonic Treatment;Mechanical Properties
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发布时间：2024-04-01 - 摘要：Al-xZn-8 Si-2 Cu（x=12,14,16,18,/%） alloy profiles were fabricated by die casting. The effects of different Zn contents on the microstructure morphology of the alloy were analyzed by OM and SEM, and the influence of Zn content on mechanical properties and thermal conductivity were further analyzed. The results indicate that when the Zn content of alloy is increased from 12% to 18%, the Zn solid solution in α-Al matrix is increased, playing a role of solid solution strengthening. Meanwhile, the dimension of eutectic Si phase is increased to form a sharp angle, resulting in stress concentration. The tensile strength and yield strength of the alloy are increased from 345.5 MPa and 263.5 MPa to 395.4 MPa and 343.8 MPa, respectively, and the elongation is decreased slightly. Meanwhile, the thermal conductivity is decreased from 109.4 W/（m·K） to 85.7 W/（m·K）.关键词：Aluminum Alloy;Zn Element;Thermal Conductivity;Mechanical Properties;Microstructure
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发布时间：2024-04-01 - 摘要：The characteristics of Al2Cu phase in casting A319 alloy were analyzed by high-precision three-dimensional X-ray computed tomography, and the effects of different Cu contents and cooling rates on the three-dimensional characteristics of Al2Cu phase were quantitatively characterized. The results indicate that in the specimens with higher Cu content and lower cooling rate, the variation trend of the three-dimensional characteristics of the Al2Cu particles is similiar. In terms of the size and amounts, the average and maximum volume of Al2Cu particles is larger, and the amount is fewer. In terms of morphology, the compactness of particles is increased and the specific surface area is decreased, which means that the structure is more compact with a fewer branches, and the complexity of morphology is reduced. However, comparing with the increase of Cu content, the decrease of cooling rate leads to the significant variation in above-mentioned size, amount and morphology, which is prone to increase the inhomogeneity of Al2Cu particle morphology and spatial distribution.关键词：A319 Alloy;Al2Cu Phase;Cooling Rate;3D X-ray Computed Tomography
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发布时间：2024-04-01 - 摘要：The low-temperature aging treatment experiments of AlSi7 CuMnMg die-casting aluminum alloy were carried out, and strength and toughness index K was introduced to analyze the mechanical properties of the alloy under various aging treatment conditions. The results show that with the increase of the aging temperature（150～180 ℃） and the extension of the aging time（2 h～10 h）, the yield strength of the alloy is increased significantly, while the plasticity is decreased.The optimal low temperature aging process of the alloy is determined to be 170 ℃×6 h, where the tensile strength is 303 MPa, and yield strength reaches 183 MPa, which is 40.77% higher than that of the as-cast state, and the elongation is 7.5%. The strength of the alloy is improved with the satisfied plasticity.关键词：AlSi7CuMnMg Alloy;Die-Casting Aluminum Alloy;Aging Treatment;Mechanical Properties
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发布时间：2024-04-01 - 摘要：The effects of Y on the isothermal oxidation behavior of a nickel-based single crystal superalloy containing Re at 900 ℃, 1 000 ℃ and 1 100 ℃ were investigated by static weight gain method. The microstructure and morphology of oxidation were analyzed by X-ray diffraction（XRD） and scanning electron microscope（SEM）. The results indicate that oxidation grade of the alloy with yttrium and without yttrium are all complete oxidation resistance grade at 900 ℃, 1 000 ℃ and 1 100 ℃. The oxidation weight gain at 900 ℃ and 1 000 ℃ are hardly affected, while that at 1 100 ℃ is significantly reduced by the increase of Y content, which is attributed to the continuity increase of α-Al2O3 caused by Y addition, enhancing the protective effect of oxide film.关键词：Single Crystal Superalloy;Yttrium;Isothermal Oxidation
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发布时间：2024-04-01 - 摘要：Aiming at anodic oxidation of 5083 aluminum alloy casting plate to form the color difference of the ingot cross section, the influence of different casting temperatures and casting speeds on the oxidation color difference was compared by oxidation test, and the water-immersed ultrasonic C-scan testing equipment was applied to detect the flat ingot. Sampling at different locations, the defects were analyzed by optical microscope, scanning electron microscope and energy dispersing spectrometer. The results indicate that the color difference occurs in the range of 1/3 to 1/4 thickness layer of flat ingot, and there exists a larger degree of component segregation, massive metal compound and higher solid hydrogen content compared with the normal area.In addition, the color difference formed in the subsequent anodic oxidation process of the casting plate can be effectively reduced by increasing the casting temperature, reducing the casting speed and decreasing the hydrogen content of the solution appropriately, enhancing the yield rate.关键词：5083 Aluminum Alloy;Casting Plate;Ultrasonic;Defect Analysis;Oxidation Color Difference
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发布时间：2024-04-01 - 摘要：The as-cast SAC305（Sn3.0 Ag0.5 Cu） lead-free solder was compressed at constant temperature（20～140 ℃） by UTM6202 electronic universal testing machine. According to the experimental data under different working conditions, the flow stress, strain rate and deformation temperature of lead-free solder were fitted, and the parameters of Arrhenius constitutive equation were calculated. The results reveal that the true stress-strain relationship of lead-free solder SAC305 is significantly correlated with temperature and strain rate. The yield strength of solder is decreased with the increase of strain temperature and increased with the increase of strain rate. The stress-strain relationship of lead-free solder measured at the strain rates of 5×10-4 s-1 and 5×10-5 s-1 was compared with the experimental ones, and the calculated values were consistent with the experimental ones, indicating that the hyperbolic sine constitutive relation can be used to describe the flow stress of lead-free solder during hot compression deformation, where the thermal deformation activation energy Q is 61.863 23 kJ/mol.关键词：SAC305 Lead-free Solder;Compression Properties;Flow Stress;Mechanical Properties
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发布时间：2024-04-01 - 摘要：7050-T7451 aluminum alloy super-thick plate with thickness of 200 mm was taken as the research object, and samples were cut from different thickness and different orientation to investigate the microstructure characteristics of aluminum alloy at different sampling positions. Then the samples were anodized in sulfuric acid, and the influence of sampling position on corrosion resistance of anodic alumina film was also analyzed. The corrosion resistance was evaluated by potentiodynamic polarization and electrochemical impedance spectroscopy（EIS）. The results reveal that the microstructure of the aluminum alloy samples is different to some extent from the surface to the center. After anodizing, the corrosion current density of L-T surface is the lowest, while the impedance is the highest, indicating the desirable corrosion resistance.关键词：7050 Aluminum Alloy;Extra-thick Plate;Sampling Position;Anodic Film;Corrosion Resistance
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发布时间：2024-04-01 - 摘要：The solidification structure and properties of Cu-1.7 Ni-0.2 Co-xBe alloy with low beryllium addition were investigated by OM, XRD, SEM, universal tensile testing machine and conductivity measurement instrument. The results indicate that when the addition of Be is in the range of 0.4%～0.7%, the macrostructure of the alloy is refined with the increase of Be addition, and the secondary dendrite arm spacing is decreased continuously from 31.85 μm to 16.58 μm. The tensile strength of the alloy is increased at first and then decreased, which reaches the maximum of 490.4 MPa with the 0.5% addition of Be, and the elongation is increased gradually. The conductivity of the alloy is decreased at first and then increased, which reaches the minimum value of 18.792 MS/m when the addition of Be is 0.5%. BeNi phase can be observed in the alloy when the addition of Be is more than 0.5%.关键词：Low Beryllium Copper;Solidification Structure;Tensile Strength;Elongation;Conductivity
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发布时间：2024-04-01 - 摘要：The interpenetrating network SiC/Al-Mg composites were prepared by 3 D-printed network SiC preform combined with the melt infiltration process of Al-Mg alloy. The microstructure, mechanical properties and friction properties of the composites were characterized, and the effects of infiltration temperature was analyzed. The results indicate that Al alloy can fully permeate SiC with 3 D printed hierarchical network structure from 910 ℃ to 950 ℃, and the microstructure of composite is composed of interpenetrating Al alloy and “shell-core” network frame. The increase of infiltration temperature promotes the reaction and the uniformity of microstructure. When the temperature is 930 ℃, the SiC/Al-Mg composite has the optimal comprehensive properties, where compressive strength and hardness of the composites reach 425 MPa and 557 HV, respectively, and the wear rate is 3.37×10-7 cm~3/（N·m）.关键词：Interpenetrating Network Structure;3D Printing;Microstructure;Mechanical Properties
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发布时间：2024-04-01 - 摘要：Taking domestic carbon fiber M55 J as reinforcement and ZL301 as matrix alloy, three-dimensional five-directional M55 J/Al composites were fabricated by vacuum pressure infiltration method. The compactness and microstructure of the composites as well as the tensile properties were investigated at room temperature and high temperature（350 ℃）. The fiber dimension was extracted from the composites to observe and analyze fiber damage. The results indicate that the compactness of the three-dimensional five-directional M55 J/Al composite is 97.8% with desirable infiltration effect. After impregnation, the mean tensile strength and modulus of M55 J monofilament reach 3 440 MPa and 513 GPa, respectively, which are slightly lower than those of precursor. The tensile strength and modulus of three-dimensional five-directional M55 J/Al composites are 601.3 MPa, 689.7 MPa, and 181.6 GPa, 146.7 GPa, respectively at room temperature and 350 ℃. The high temperature strength may be attributed to the reduced binding of matrix to braided yarn and absence of bending and necking phenomenon.关键词：Domestic Carbon Fiber;Cf/Al Composite;Vacuum Pressure Infiltration;Microstructure;Mechanical Properties
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发布时间：2024-04-01 - 摘要：The processing cost of a special shaped shell is high as a result of large size, expersive material and only about 10% in material utitization. In order to improve the utilization rate of materials, a new forming scheme was designed based on its structural characteristics: blanking-bottom forming-thin wall part forming-deep drawing-mechanical processing. In the process of bottom forming, the punching-turning-squeeze method and even skin method were designed, respectively. In thin wall forming, the material utilization rate could be improved by reducing machining allowance. Using numerical simulation method to analyze the load, equivalent stress in different solutions, different blank thickness and different part, appropriate process was chosen according to the practical conditions to improve the material utilization by 4 times.关键词：Numerical Simulation;Forming Process;Material Utilization Rate;Structural Characteristics
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发布时间：2024-04-01 - 摘要：3D geometry design of steel casting riser processes based on OpenCascade was carried out. Meanwhile, different riser design systems were selected according to modulus calculation of steel castings and different riser types, realizing rapid design for steel casting riser system. Firstly, the 3D model of steel casting was read and the whole modulus was calculated. Then, different interception types were set and the profile as well as the locationare were determined through the parameterized design of the system, thus obtaining the local modulus of the casting interception. Next, the 3D model of the riser was automatically established by combining the local modulus and the selected riser type. Finally, taking actual steel castings as an example, the feasibility of the riser design system was verified. The results indicate that the riser design system can improve riser design efficiency, shortening the design period.关键词：Open Cascade;Riser Design;Modulus;Steel Casting
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发布时间：2024-04-01 - 摘要：The traditional water-glass sand type has disadvantages of low recycling rate, poor storage stability and serious environmental pollution. A combination of selective laser sintering and impregnation reinforcement technology was adopted to develop a graphite ceramic composite type with low thermal conductivity and high strength, intending to replace the water-glass sand type and reduce the environmental pressure. The graphite-ceramic composite type was designed based on a theoretical model of tandem thermal conductivity, and the relationship between different functional layer thicknesses and thermal conductivity coefficient were determined. The effects of graphite/phenolic resin hybrid powder composition and silica-sol impregnation reinforcement process were investigated on the thermal conductivity coefficient and compressive strength of the sparse thermal insulation layer and the impregnation reinforced layer. Finally, graphite-ceramic composite types with thermal conductivity coefficient less than 2 W/（m·K） and compressive strength higher than 10 MPa were rapidly prepared, and pouring was conducted, verifying the feasibility of replacing water-glass sand types with graphite-ceramic composite types.关键词：Graphite Ceramic Composite;SLS;Impregnation Reinforcement;Thermal Conductivity Coefficient
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发布时间：2024-04-01 - 摘要：In order to determine the optimal process parameters of H13 steel by WAAM single-layer and single-pass forming, the experimental combination of deposition current of 80～240 A and deposition speed of 2～6 mm/s, the experimental combination of 5%O2+95%Ar, 10%CO2+90%Ar and 20%CO2+80%Ar were selected on the H13 steel substrate after quenching and tempering treatment. The influence of process parameters on the forming of single-layer single-pass layer was analyzed through evaluation indexes of reinforcement coefficient and forming coefficient. The results indicate that the reinforcement coefficient and forming coefficient are decreased with the increase of deposition current, and the reinforcement coefficient reaches the maximum of 3.79 under the experimental combination of 120 A and 6 mm/s, which reaches the minimum of 2.11 at 240 A and 6 mm/s. The forming coefficient reaches the maximum of 8.56 under the experimental combination of 80 A and 2 mm/s, which reaches the minimum of 3.42 at 200 A and 6 mm/s. Therefore, when deposition current is 120 A, deposition speed is 4 mm/s and protective gas is combination of 20%CO2+80%Ar, forming parts with desirable quality can be obtained.关键词：Arc Additive Manufacture;Wire;Reinforcement Coefficient;Forming Coefficient
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发布时间：2024-04-01 - 摘要：The dimensional accuracy of ceramic core directly affects the wall thickness of hollow blade wax mold. The numerical simulation method of ceramic core injection molding for large-scale single crystal blade of gas turbine was conducted, and the filling process, volume shrinkage and warpage deformation were predicted. The data model of injection parameters and average volume shrinkage was established based on the experimental design. The results indicate that the influence order of each process parameter on the average volume shrinkage presents as follows: injection temperature > holding pressure > injection rate. The optimal wax injection process parameters are holding pressure of 3.483 MPa, injection temperature of 139.84 ℃, and injection rate of 258.60 cm~3/s, so the dimensional accuracy of ceramic core reaches CT3 level.关键词：Ceramic Core;Injection Parameters;Numerical Simulation;Dimensional Accuracy
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发布时间：2024-04-01 - 摘要：The effects of coating technology on filling capacity of graphite casting and the quality of titanium alloy casting was investigated. The results indicate that the liquid dispersion of the titanium alloy is more uniform and stable after the coated graphite mold, and the filling ability of the thin plate is improved, effectively reducing the flow mark and cold shut defects on the surface of castings and improving the surface roughness, which is increased from 12.5 μm to 6.3 μm. Surface crack formation of castings is effectively avoided, and good adhesion with graphite is obtained without slag dropping. The metallographic examination demonstrates that the thickness of the diffusion layer on the surface of the casting is equivalent to that of the uncoated one, both of which are less than 0.05 mm.关键词：Coating;Graphite Casting;Titanium Alloy
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发布时间：2024-04-01 - 摘要：A380 aluminum alloy was adopted to manufacture thin-wall shell with high precision and lightweight in LK cold chamber die casting machine. At the same time, through determing influencing factors and level, testing experiment was designed rationally. The optimized processing parameters were presnted as follows: filling velocity of 0.2 m/s, pressization time of 5 s and injection specific pressure of 60 MPa by orthogonal design to produce the qualified die casting thin-walled A380 housing.关键词：A380 Alloy;Thin-wall Shell;Die Casting;Orthogonal Experiment;Process Parameters
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发布时间：2024-04-01 - 摘要：Aiming at the pre-designed gating system of an automobile oil pan die casting, based on reducing the leakage of high-pressure oil passage and improving the internal shrinkage cavity and air hole of the casting, the traditional design scheme and the improved design scheme were simulated, and the optimal scheme meeting the casting quality requirements was screened after computer automatic calculation and comparison of results. It has been verified by experiments that a new type of super-point cooling could be adopted in local positions, and the internal quality of castings could be improved obviously by adopting the improved scheme design. Meanwhile, the qualified rate of castings could be improved, shortening the period of quality improvement.关键词：Die;Die-Casting Aluminum Alloy;Super-point Cooling;Numerical Simulation
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发布时间：2024-04-01 - 摘要：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。广告业务范围（1）铸造合金材料；（2）铸造原辅材料；（3）熔炼设备；
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发布时间：2024-04-01
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