共查询到20条相似文献,搜索用时 47 毫秒
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基于分散相粒子运动模型,考虑夹渣在随流运动过程中动态聚合长大现象,构建了夹渣聚合长大模型(PAGM,Particles Aggregation Growth Model)。采用PAGM对铝合金螺旋桨铸件浇注过程中夹渣的运动轨迹、聚合长大行为及最终位置进行了模拟计算和试验验证。在此基础上研究了浇注系统对铸件夹渣分布及夹渣率的影响。结果表明,浇注系统设计对夹渣运动行为及分布有较大影响,PAGM可有效提升对铸件夹渣分布预测的准确性,为铸件优化设计及失效分析提供参考。 相似文献
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针对Makino铣床床身铸造工艺,利用Anycasting软件模拟了铸件的充型和凝固过程,分析了铸件成形过程中内部温度场、流场的变化规律。通过综合考虑浇注温度(1 280、1 320、1 360和1 400℃)和充型速度(1.0、1.2和1.4m/s)对成形的影响,得出浇注温度和充型速度对铸件品质的影响。结果表明,采用优化浇注工艺参数(浇注温度为1 320℃,充型速度为1.2m/s),在合理位置处设置冒口,把最后凝固位置控制在冒口内部,可解决气孔缺陷。以铸件内部温度场分布为依据,减小了铸件缩孔倾向,为实际生产提供参考。 相似文献
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从灰铸铁床头箱铸件的结构和技术要求出发,阐述了该件铸造工艺设计过程,并使用UG软件对床头箱零件的三维结构和浇冒口系统进行建模。综合比较浇注位置及分型面位置,采用了半封闭底注式浇注方案,借助ProCAST软件对铸件的充型和凝固过程进行模拟分析,并对冒口和冷铁的尺寸和位置进行了优化设计。结果表明,采用底注式浇注方案,铸件充型平稳且完整,能有效避免浇不足、冲砂等缺陷。优化后的冒口和冷铁使铸件具有合理的凝固顺序,冒口作为最后凝固部位,可望消除重要加工面的缩松缩孔缺陷,确保床头箱铸件的质量要求。 相似文献
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Ata Fallah-Mehrjardi Peter C. Hayes Evgueni Jak 《JOM Journal of the Minerals, Metals and Materials Society》2014,66(9):1654-1663
Slag freeze linings, the formation of protective deposit layers on the inner walls of furnaces and reactors, are increasingly used in industrial pyrometallurgical processes to ensure that furnace integrity is maintained in these aggressive, high-temperature environments. Most previous studies of freeze-linings have analyzed the formation of slag deposits based solely on heat transfer considerations. These thermal models have assumed that the interface between the stationary frozen layer and the agitated molten bath at steady-state deposit thickness consists of the primary phase, which stays in contact with the bulk liquid at the liquidus temperature. Recent experimental studies, however, have clearly demonstrated that the temperature of the deposit/liquid bath interface can be lower than the liquidus temperature of the bulk liquid. A conceptual framework has been proposed to explain the observations and the factors influencing the microstructure and the temperature of the interface at steady-state conditions. The observations are consistent with a dynamic steady state that is a balance between (I) the rate of nucleation and growth of solids on detached crystals in a subliquidus layer as this fluid material moves toward the stagnant deposit interface and (II) the dissolution of these detached crystals as they are transported away from the interface by turbulent eddies. It is argued that the assumption that the interface temperature is the liquidus of the bulk material represents only a limiting condition, and that the interface temperature can be between T liquidus and T solidus depending on the process conditions and bath chemistry. These findings have implications for the modeling approach and boundary conditions required to accurately describe these systems. They also indicate the opportunity to integrate considerations of heat and mass flows with the selection of melt chemistries in the design of future high temperature industrial reactors. 相似文献
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Outlining procedures for the magnesium-reduction process with particular emphasis on techniques developed by Osaka Titanium Co. 相似文献
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PHOSPHORUS REMOVAL USING STEEL SLAG 总被引:7,自引:0,他引:7
R.W. Smith 《金属学报(英文版)》2006,19(6):449-454
1. Introduction Atpresent,eutrophication of water bodies is a serious environmental issue in almost all the countries of the world. Previous studies have proved the phosphorus from some industrial waste water and living wastewateristhemaincontrollingfactorintheeutrophicationofwaterbodies;sotheremovalofphospho- rus in waste water is essential to prevent the eutrophication of water bodies. ThecurrentmethodsofphosphorusremovalinChinaandabroadincludeprecipitation,crystallization, ion exchange, bio… 相似文献
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Kamekichi Wada 《JOM Journal of the Minerals, Metals and Materials Society》1959,11(3):187-188
Economics of steel production in Japan are such that this large producer has found means of utilizing some two-thirds of its open-hearth slag. 相似文献
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转炉钢渣是转炉冶炼过程中的产物,是一种固体废弃物,占钢产量的10%左右。我国钢渣的综合利用率仅在10%左右。目前转炉钢渣的初步处理方法较多,转炉炼钢过程中,因造渣形成的液态转炉渣具有一定的黏性而夹裹部分金属铁,长期堆存渣场会占用场地,不能有效回收金属铁又会造成资源的浪费。焖渣法就是利用钢渣余热,在有盖容器内加入冷水后使其成为蒸汽,使钢渣得到消解,通过膨胀冷缩达到渣铁分离。处理后的钢渣,性能稳定,消除游离态CaO对钢渣性能的影响,可作为钢渣微粉、钢渣砖等的原料。 相似文献