共查询到20条相似文献,搜索用时 859 毫秒
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Gerrit BEHRENS Julien KOVAC Bernd KHLER Frank VOLLERTSEN Heinz-Rolf STOCK 《中国有色金属学会会刊》2012,(Z2):268-274
拉深成形可以用来制备形状复杂的零部件,甚至可达微加工水平。采用磁控溅射方法,在基底温度分别为310K和433K下,制备了厚度约为15μm的两种不同的AlZr薄膜。将这两种薄膜做为坯料,采用冲头直径为0.75mm的微拉深设备研究其拉深性能。虽然这两种材料在拉伸试验中显示出较小的最大应变,但还是成功地实现了微拉深成形。在基底温度为310K和433K制备的两种材料的极限拉深比分别为1.8和1.7。这些结果比先前采用AlSc合金的结果要好,与采用传统轧制方法所得纯铝薄膜的拉深结果相似。结果表明,采用磁控溅射方法制备的薄膜可以用来进行微拉深成形。 相似文献
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胡道春 《锻压装备与制造技术》2015,50(1)
本设计零件为筒盖,是三级阶梯拉深和一反拉深、浅正拉深及冲孔的拉深件,结构较复杂,在分析成形工艺基础上,采用两套复合模。由于拉深成形时会出现拉裂、起皱等问题,因此设计时设计压边圈,避免了零件起皱;利用模拟软件分析材料成形工艺,以确定所设计模具是否会拉裂,减少不必要的损失;对筒盖进行三维造型,可以解决零件结构复杂、毛坯尺寸计算繁琐的问题。 相似文献
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针对AZ31B镁合金方盒形件进行拉深成形工艺试验,分析了单个工艺参数的变化对盒形件拉深成形过程的影响,在其他因素不变的条件下,凹模温度在150~300℃范围内,成形深度随温度升高而增大,在300℃时成形深度达到最大值;凸模温度保持在120℃左右,差温拉深效果较为明显;压边间隙调整到1.3t(t为板材厚度)时,拉深深度最大;拉深速度在30 mm·min-1时成形深度最大。确定了影响拉深成形深度的各工艺参数的先后顺序为:压边间隙、凸模温度、凹模温度和拉深速度。运用正交试验方法进行各工艺参数优化组合,结果表明,采用最优工艺参数组合可以提高AZ31B镁合金方盒形件拉深成形的成形深度。 相似文献
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A. Anil Kumar Satyanarayan Satapathy D. Ravi Kumar 《Journal of Materials Engineering and Performance》2010,19(8):1150-1160
The importance of hydromechanical deep drawing is due to certain advantages over conventional deep drawing such as better formability, reduced number of manufacturing steps, improved surface finish, etc. Due to this, the potential applications of hydromechanical deep drawing have increased in the recent years. In this process, sheet metal parts are formed with the assistance of fluid pressure. The present work addresses the effect of sheet thickness and punch roughness on the formability of interstitial-free steel sheets in hydromechanical deep drawing. Experimental work has been done to study the influence of counter pressure on drawability by varying the sheet thickness and punch roughness. Finite element method has been used to simulate the process, and the results have been found to be in good agreement with the experimental results. It has been found out that the minimum required counter pressure for successful drawing increases with increase in sheet thickness. Drawability of 1.2 mm thick sheet improved with increase in punch roughness. As the punch roughness increases, the minimum required counter pressure decreases because of improved friction holding effect. For the same punch roughness, the minimum required counter pressure increases with increase in draw ratio. 相似文献
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轴对称曲面件智能化拉深成形过程的解析定量描述 总被引:22,自引:4,他引:18
成形过程的定量描述是板材成形智能化控制中在线识别材料参数和工况参数以及预测最佳工艺参数的理论依据,识别和预测精度取决于定量描述的准确程度。为了实现轴对称曲面件拉深过程的智能化控制,分析了轴对称曲面拉深件的共性特征,建立了完整的力学模型,在直线假设、面积不变假设和似直梁弯曲假设条件下,给出了拉深过程中拉深力-行程曲线的解析定量描述。用三种板材以锥形件拉深为例进行了实验验证。 相似文献
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变压边力拉深的原理及实验系统 总被引:27,自引:6,他引:21
板料拉深过程中,压边力是一种重要的工艺参数。由于其在冲压拉深过程中的重要作用及在生产中易于调节、控制,近年来一些汽车工业较为发达的国家,正在进行着变压边力拉深新工艺方法的研究。本文从板料冲压拉深过程对压边力需求的分析中,提出了变压边力控制方法的原理,建立了变压边力拉深实验系统,并以圆锥形件为研究对象对拉深过程中合理的变压边力控制问题进行了探索性研究,取得了阶段性成果。 相似文献
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Deep drawing of non-axisymmetric cross-section cups from thin sheets or metal foils has become increasingly important, especially for miniaturization of mechanical components. However, with a thin sheet thickness, conventional deep drawing processes are not able to offer reasonable drawing ratios due to early formations of localized wrinkling and fractures at cup corners. In this paper, a friction aided deep drawing process has been developed to increase the deep drawability of thin sheets and metal foils. Productions of square cups have been chosen to verify the current proposed process since the shape provides recognizable non-homogeneous deformation, which can then be compared to conventional processes. In the proposed process, a circular blank holder of a square hole is divided into eight identical segments of 45°. During the deep drawing process, four of the eight segments will move radially inward while the other four segments will move radially outwards cyclically under a pre-determined blank holding pressure. A finite element model of the technique was used to simulate virtual experiments to evaluate and optimize the controlling parameters that influence the cup height and forming process. Taguchi and Pareto ANOVA statistical methods were subsequently used to determine the optimum conditions for best cup height. The results have shown that the new technique is capable of producing deep square cups from soft aluminum sheet (Al-O) of 0.5 mm thickness with a high drawing ratio of 3.3. In addition, it was also observed that the radial displacement was the most significant parameter in influencing the cup height. 相似文献
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AZ31B镁合金薄板拉深成形模拟分析 总被引:1,自引:0,他引:1
用Dyanform软件模拟AZ31B镁合金的拉深成形过程,通过自动设置模块进行参数设置,并最终得到接近实验结果的变形过程、成形极限以及壁厚分布趋势。模拟结果表明:基于Dynaform的数值模拟可以用于镁合金的成形过程分析及试件破损预测等,对于指导拉深物理实验具有重要作用。 相似文献
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本文总结了影响板料成形性能的因素并指出相应改善方法 ,重点研究了压边圈形变对板料成形性能的影响 ,并指出考虑BH形变的BHF控制是压边力控制研究的方向。 相似文献
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将拉延筋模型引入到板料成形动力显式有限元分析中,并以汽车前照灯矩形反光镜为应用实例,对其拉延成形过程进行了模拟。 相似文献
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响应面法在多次拉深成形参数优化中的应用 总被引:1,自引:0,他引:1
引入最小二乘响应面法建立薄板多次拉深成形参数优化方法.利用ANSYS/LS-DYNA有限元显式程序模拟板料多次拉深成形的高度非线性行为,以第一次的拉深系数和凸模圆角半径为设计变量,以两次板料拉深成形过程中使板料厚度变薄最少为目标,采用九点中心对称试验方法选取样本点,运用最小二乘响应面法构造响应面近似模型.研究结果表明,响应面法应用在薄板拉深成形参数优化问题上是可行的,可在设计域内快速寻优,具有提高计算效率、缩短设计周期、减少生产成本等优点. 相似文献