共查询到18条相似文献,搜索用时 156 毫秒
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提出了基于往复式喷射成形工艺制备大璧厚非规则管坯的近终形成形工艺及其工艺参数优化方法,以实现坯件从CAD设计到喷射成形的快速制备过程。该工艺方法包括三个阶段:非规则管坯的三维CAD设计、分层处理和单层沉积厚度计算;基于沉积厚度与往复速度和质量流率的对应关系,计算满足各层沉积厚度所对应的控制参数;利用控制系统和执行机构对控制参数进行实时控制和调节,采用往复式多层喷射成形工艺制备满足设计轮廓的管坯。通过试验进行了验证,喷射成形制备的管坯形状和轮廓与CAD设计模型较好地一致,表明了该工艺方法的可行和正确性。 相似文献
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Modeling of spray-formed materials: Geometrical considerations 总被引:3,自引:0,他引:3
Y. J. Lin E. J. Lavernia J. E. Bobrow D. R. White 《Metallurgical and Materials Transactions A》2000,31(11):2917-2929
In this article, a mathematical model is formulated to predict the evolution and final geometry of an axisymmetric billet
(i.e., round) obtained using an off-axis spray arrangement. The model is formulated by calculating the shape change of a profile
curve of a billet surface, based on an axisymmetric surface. On the basis of this model, a methodology to determine the “shadowing
effect” coefficient is presented. The modeling results suggest that there are three distinct regions in a spray-formed billet:
a base transition region, a uniform diameter region, and an upper transition region. The effects of several important processing
parameters, such as the withdrawal velocity of substrate, maximum deposition rate, spray distribution coefficient, initial
eccentric distance, and rotational velocity of substrate, on the shape factors (e.g., the diameter size of the uniform region and the geometry of the transition regions) are investigated. The mechanisms responsible
for the formation of the three distinct regions are discussed. Finally, the model is then implemented and a methodology is
formulated to establish optimal processing parameters during spray forming, paying particular attention to deposition efficiency. 相似文献
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A three-dimensional model of the spray forming method 总被引:2,自引:0,他引:2
Hyun-Kwang Seok Kyu Hwan Oh Hyung Yong Ra Dong-Hun Yeo Ho-In Lee 《Metallurgical and Materials Transactions B》1998,29(3):699-708
A three-dimensional model has been formulated to calculate the shape of the general preform, using vector calculus. The shape
of a rod, tube, plate, or irregular preform can be calculated at given spray forming conditions. The shape of a spray-formed
rod was analyzed at various spray forming conditions using the three-dimensional model. The effects of spray forming parameters,
such as spray distribution parameters, angular velocity of rotation, withdrawal velocity, spray angle, and eccentric distance
on rod shape, were analyzed. The most important parameters affecting the shape of rods are the spray distribution parameters
and the withdrawal velocity. The dynamic evolution of rod shape with a stepwise variation of the withdrawal velocity during
spray forming was investigated. The effect of a stepwise change of the withdrawal velocity was the same as that of the scanning
atomizer. The calculated surface profiles were compared with those of spray-formed 7075 aluminum alloy rods prepared on a
pilot scale. The calculated results for the surface profiles were in agreement with those of the spray-formed rods. 相似文献
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REN Sanbing FAN Junfei LE Hairong Advanced Technology Division Research Institute Baoshan Iron & Steel Co. Ltd. Shanghai China 《Baosteel Technical Research》2011,5(3):15-19
Spray forming is a new type of metal material forming process,which can produce metal blanks such as billet,tube,plate etc.A mathematical model has been developed to forecast the shape evolution of tube billets during the spray forming process.The atomizer mass flux as,radial distribution coefficient bs,draw velocity and diameter of mandrel were considered in this model and the influence of different parameters such as metal flowrate,draw velocity of mandrel,diameter of mandrel on the tube’s shape change were simulated and analyzed in this paper.The simulation results obtained from this model can be provided to engineers as reference. 相似文献
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Hyun-Kwang Seok Jae-Chul Lee Ho-In Lee Hui Choon Lee Kyu Hwan Oh Hyung Yong Ra 《Metallurgical and Materials Transactions A》2000,31(5):1479-1488
In rod spray forming, the preform changes its shape continually from that of a disc to a rod (transient-state rod growth)
and then maintains its top surface profile once it has settled down (steady-state rod growth). The rod growth mechanism during
spray forming was analyzed using rod-forming models. At a sufficiently high substrate rotation velocity, the calculated results
based on the three-dimensional time-dependent model (3-D TDM) and the two-dimensional time-dependent model (2-D TDM) were
observed to be identical. The calculated results of the rod’s top shape, obtained by the TDMs, were almost identical to those
obtained by the two-dimensional time-independent model (2-D TIM), which means that there exists steady-state rod growth. The
effects of spray-forming parameters, such as initial eccentric distance, substrate withdrawal velocity, and spray angle, on
the shape-evolution behavior were analyzed in terms of the vertex growth velocity (
). The optimum spray-forming condition to minimize transient-state rod growth was also presented. Experimental verification
was made to confirm the proposed forming models. 相似文献
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Metal Spray Forming Process Examined Using Mathematical Model 总被引:1,自引:1,他引:0
The metal spray forming process was examined using the mathematical model simulation by Baosteel's test and developed facilities.The mathematical model comprised of the probability and statistical analysis of the droplet mass behavior and predicted the shape and temperature distribution of the billet during the spray forming process. 相似文献
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ZHANG Yin ) FAN Junfei ) REN Sanbin ) ) Inner Mongolia Key Laboratory for Utilization of Bayan Obo Multi-Metallic Resources Inner Mongolia University of Science Technology Baotou Inner Mongolia China; ) School of Rare Earth Inner Mongolia University of Science Technology Baotou Inner Mongolia China ) Advanced Technology Division Research Institute Baoshan Iron & Steel Co. Ltd. Shanghai China 《Baosteel Technical Research》2011,5(3):9-14
The metal spray forming process was examined using mathematical simulation and verified through the prototyping evaluation at Baosteel’s test and development facilities.The mathematical model comprised of four sections,including jet gas flow in the deposition chamber;single droplet behavior along its trajectory path;probability and statistical analysis of droplet mass behavior,and forecast of the shape and temperature distribution of the billet during the spray forming process. 相似文献