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Zuo Kesheng Zhang Haitao Qin Ke Cui Jianzhong Chen Qingzhang 《Metallurgical and Materials Transactions B》2017,48(1):429-443
Metallurgical and Materials Transactions B - A three-dimensional CFD model coupled with melt flow, heat transfer, and thermal contraction was developed to simulate the direct-chill (DC) casting... 相似文献
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介绍了铝合金挤压制品,特别是空心型材制品的干燥封存技术的防腐蚀机理、包装的工艺特点及检验方法以及推广运用的前景和意义。 相似文献
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7001合金Zn+Mg+Cu在11~14%之间,裂纹倾向性非常大,铸锭成型困难,裂纹严重。主要与合金的性质,包括主要成分和杂质的控制、铸造工艺的制定以及操作人员的操作水平;铸造工具的选择等有直接的关系。 相似文献
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文章阐述了5182铝合金熔炼过程中合金成分的保证、熔体除钠、除氢工艺,氧化夹杂物的净化等工艺,并通过试验研究优化了5182合金大规格扁锭的铸造工艺参数。 相似文献
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E. Jayakumar T. P. D. Rajan B. C. Pai 《Transactions of the Indian Institute of Metals》2012,65(6):677-681
Hypereutectic Al?CSi alloys are used in components that require high resistance wear and corrosion, good mechanical properties, low thermal expansion and less density. The size and morphology of hard primary silicon particles present in Al?CSi alloys greatly influences the mechanical properties. Addition of Mg leads to formation of intermetallic Mg2Si phases, which contributes towards the properties of high silicon alloy as well as alters the nature and quantity of primary silicon formed. The high silicon alloy subjected to centrifugal casting leads to the formation of functionally gradient material, which provides variation in spatial and continuous distribution of primary phases in a definite direction exhibiting selective properties and functions within a component. The present study is to evaluate the effect of Mg on solidification microstructures of homogenous and functionally graded A390 aluminium alloys. The addition of Mg from 3 to 5?% in A390 alloy using Al?C20Mg master alloy has shown a transformation from primary silicon rich matrix to Mg2Si rich matrix. Centrifugal casting shows the gradient distribution of primary silicon and Mg2Si phases towards the inner periphery of the casting. 相似文献
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通过激光扫描共焦显微镜、X射线衍射、扫描电镜、电子探针、微区成分能谱分析和差示扫描量热法,研究了高合金Vanadis4(V4)模具钢(%:1.5C、8.0Cr、1.5Mo、4.0V)的凝固过程及其微观组织。结果表明,V4钢基体为马氏体和残余奥氏体,基体中碳化物主要为MC与M7C3型。杆状、棒状或团块状VC分布在晶界。该钢在凝固时,首先发生结晶过程L→γ从液相中析出初生γ相,随着γ相不断析出,剩余液相中合金元素含量不断富集,达到共晶成分后将先后发生L→γ+MC与L→γ+M7C3共晶反应。 相似文献
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锻造工艺参数对7050铝合金再结晶行为的影响 总被引:1,自引:0,他引:1
利用Gleeble-1500热模拟实验机对7050铝合金进行了等温压缩实验,与有限元仿真软件DEFORM3D模拟实验相结合,通过应力-应变与组织分析研究了7050铝合金在不同锻造工艺参数条件下的再结晶行为,结果表明,通过改变温度和应变速率能有效控制再结晶体积分数和晶粒尺寸。 相似文献
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文章从中空玻璃铝隔条加工成型工艺和终端客户使用要求出发,分别选择热轧坯料和铸轧坯料进行分组试验,重点对机械性能和表面亮度进行了研究,确定了两种规格和合金状态最佳的坯料选择、生产流程与工艺参数等控制措施。 相似文献
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分析了6005A铝合金655mm×260mm扁挤压锭裂纹的形貌、分布、形成原因,通过改进分配漏斗、喇叭嘴,调整铸锭大、小面凝固收缩顺序,有效地解决了扁挤压锭裂纹问题。 相似文献
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Waleed Khalifa Shimaa El-Hadad Yoshiki Tsunekawa 《Metallurgical and Materials Transactions A》2013,44(13):5817-5824
The hypereutectic Al-Si alloys constitute an important family of alloys because of their excellent wear resistance and low thermal expansion. However, the optimal microstructure and hence the optimal service performance of these alloys cannot be achieved by the conventional melt treatments used in industry today, because of the chemical incompatibility between the primary-Si refiners and the eutectic-Si modifiers used in microstructure control. The current study aimed at using ultrasonic vibrations to improve the microstructure and the properties of these alloys. The results of the current study showed that for the B390 Al-Si alloy (i) the ultrasonic treatment has potential refining effect on the primary Si and Fe intermetallic phases, (ii) the primary Si particles become finer as the pouring temperature decreases from 1033 K (760 °C) to 938 K (665 °C), (iii) pouring and ultrasonic treatment at temperatures below the start of primary Si precipitation result in the coexistence of large and fine Si particles in microstructure, (iv) phosphorous additions of 50 ppm did not show any substantial effect in the ultrasonically treated ingots, (v) ultrasonic-treated samples have uniform hardness over the surface while the untreated samples show large scattering (high standard deviation) in hardness levels and (vi) ultrasonic-treated samples showed better wear resistance in the absence of phosphorous. 相似文献
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Metallurgical and Materials Transactions B - Coupling macroscale heat transfer and fluid flow with microscale grain nucleation and crystal growth, a mixed columnar–equiaxed solidification... 相似文献
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研究了脉冲电流及Al-5Ti-B变质剂对7075铝合金铸态组织的改善和机理。结果表明,通入电脉冲及添加变质剂能抑制二次枝晶的生长,改善铸造组织的形貌,基体主要是均匀的等轴晶和近球形晶粒,同时,与直接浇铸的试样对比,合金中铜和铁元素的偏析现象得到一定程度缓解。 相似文献