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针对传统橡皮成形中设备吨位大,零件贴模度差,成形精度低等问题,提出了带水平两侧缸的分步橡皮成形方法,实现了橡皮垫的分步局部加载。基于ABAQUS有限元分析软件,在相等垂直下压量下,对比分析了传统橡皮成形和分步橡皮成形方法下零件的成形性能,同时探究了水平侧缸进给量对板材贴模度的影响,并完成了不同厚度的2A12铝合金U型件弯边实验。数值模拟与实验结果表明:在相等垂直下压量的前提下,分步橡皮成形方法有效地改善了板材贴模度,提高了成形精度,且成形力大大降低;当相对弯边高度h/t 4时,板材不宜采用橡皮成形工艺进行弯边成形;在分步橡皮垫成形过程中,为防止板料发生翘曲,水平侧缸的进给量应大于4 mm。 相似文献
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利用板材成形试验机和网格应变自动测量分析系统对热镀锌钢板进行了成形极限试验和性能分析。结果表明,锌层对热镀锌钢板胀形变形有恶化作用,应将溶去锌层后的热镀锌钢板成形曲线FLC降低至25%,来保证足够的安全域度。单向拉伸性能中应变硬化指数n值与成形性能具有较强的相关性。n值愈大,FLC越高,板料的冲压成形性能越好。结合成形极限图分析了热镀锌钢板在实际冲压成形过程中的应变区域、变形模式及安全域度。为热镀锌钢板成形性能研究提供参考。 相似文献
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《塑性工程学报》2016,(2):162-165
采用UG软件对成形塑料尼龙的高速钢车刀进行建模,并设计出特定形状的高速钢车刀。利用FANUC系统CK6140S数控车床对塑料尼龙材料进行塑性成形试验,观察塑料尼龙在特定成形参数条件下成形的运动效果及形态。利用CV3200轮廓度测量仪对成形的塑料尼龙表面进行轮廓度测量。分析通用型高速钢(W18Cr4V)车刀在不同的切削进给速度与切削深度下塑料尼龙工件的成形质量,得出最佳的切削进给速度为0.2mm·r-1、切削深度为5mm。结果表明,合理选择塑料成形刀具的材料、进给速度与切削深度,可使塑料尼龙成形呈规则完美的卷屑状,表面轮廓度与理论轮廓贴近吻合,实现塑料尼龙的高效率成形。 相似文献
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铜母线大扩展比连续挤压成形过程的数值模拟 总被引:2,自引:2,他引:0
基于连续挤压法加工铜母线是一种成形稳定、节约能源的新型铜母线生产工艺,但对于铜母线大扩展比连续挤压成形规律尚需深入研究。该连续挤压成形过程具有变形剧烈难于扩展成形的特点,因此本文针对铜母线大扩展比连续挤压成形设计了曲面过渡的阻流环结构,根据设计出的阻流环结构进行了有限元模拟分析,掌握了铜母线在大扩展比条件下的连续挤压成形规律。基于有限元模拟结果进行了连续挤压实验,成功实现了铜母线大扩展比连续挤压成形,证明了有限元数值模拟分析的重要指导价值。该模拟计算对探索复杂的铜母线大扩展比连续挤压成形规律具有重要意义。 相似文献
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工艺参数对筒形件强力旋压过程的影响 总被引:11,自引:0,他引:11
在分析筒形件强力旋压的变形特点基础上建立了计算机仿真模型,利用计算机模拟技术系统地对筒形件强力旋压过程进行了模拟,主要研究变薄率、旋轮进给量、旋轮成形角、旋轮圆角半径四个关键的工艺秘压成形过程及工件质量的影响,通过依次变化每一个参数得到一系列的塑性力学的分布效果图及相应的曲线图,并对成形缺陷进行了预测,实现了相应的参数优化。 相似文献
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本文针对铝合金板料电磁翻边工艺过程,采用数值模拟方法,研究板料上的电磁力分布特性以及几何参数对电磁力分布的影响规律,并揭示电磁力分布对翻边件成形质量的影响。结果表明,铝合金板料电磁翻边中,预制孔的存在使板料上形成电磁力边缘积聚效应,板料预制孔径和成形线圈内径参数通过改变线圈投影面积比影响电磁力分布;随着线圈投影面积比的减小,电磁力边缘积聚效应更加显著,边缘电磁力密度增大;电磁力分布较均匀时,圆角区材料塑性流动更显著,成形件能获得更高的成形高度与更小的边缘减薄率,变形区厚度分布较均匀,成形质量更好。 相似文献
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The effects of forming temperature on the formability and product properties of hot-stamping boron steel B1500HS were investigated. Based on the fractional cooling strategy, boron steel sheets were heated to achieve full austenitization before they were removed from the furnace and cooled to the forming temperature using different cooling methods. Subsequently,they were simultaneously press-formed and quenched inside the tool until the martensitic transformation was finished. A series of thermal tensile tests were conducted to study the effects of forming temperatures on the stamping performance indices, including elongation, yield ratio, and hardening exponent. Then, the mechanical properties and microstructures of the hot-stamped products were characterized. Finally, an irregular part was formed using different fractional cooling strategies, while its formability and springback phenomena were discussed. The results show that using a fast-cooling method to reach 650 °C as the forming temperature optimizes the formability of the tested B1500HS boron steel. The best mechanical properties and smallest springback values were achieved using this optimal strategy. 相似文献
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As the use of high strength sheet steels for automotive applications increases, there have been increasing occurrences of breakage on die radii at strains that are less than predicted by a conventional forming limit curve. To develop a better understanding of the problem, data from an angular stretch bend test were analyzed to determine the applied stress on a bend that caused breakage for a range of die radius, sheet thickness, and steel grade. The forming limit stress was calculated using a modified version of Stoughton's stress-based forming limit curve. The ratio of the applied failure stress to the forming limit stress is defined as the failure stress ratio. Regression analysis was used to determine the effect of the sheet thickness to die radius ratio (T/R) on the failure stress ratio for the different steel grades ranging from DDQ+ to DP980. The results were grouped due to commonality among various steel grades. Three predictive equations for (1) DP800, (2) DP980, and (3) all the other steel grades describe the behavior for all the steels in the study. It is found that breakage on a die radius for high strength steels such as DP600, DP800, and DP980 is typically a result of low values of the forming limit stress. 相似文献
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轴类件局部成形是节材、高效的精密塑性成形新工艺。在细长杆形坯料的局部成形工艺技术中,顶镦工艺应用最为广泛。当锻件变形长径比ψ>2.5时,通过一次顶镦工步完成将产生折叠,需要多次顶镦工步完成工件的成形。基于此,文章提出采用将自由镦粗、挤压、闭式模锻工艺相结合的轴类件局部成形新工艺——浮动模局部成形工艺,可避免细长杆局部镦粗工艺中的弯曲折叠,并减少成形件表面的拉应力。采用浮动模局部成形工艺可实现细长杆坯料变形长径比ψ>4的一次成形,解决了现有工艺中的一系列难题,为细长杆坯料局部精密成形提供了新的途径。 相似文献
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压出式阀门注射模设计及工艺分析 总被引:3,自引:1,他引:3
通过对压出式阀门的产品结构以及注射成形存在的工艺问题分析,选择聚苯乙烯的成形工艺参数,确定了该类塑件的注射模结构为一模四腔的结构。按聚苯乙烯的平均收缩率设计计算模具成形尺寸,在模具中设计了圆锥细纹脱模机构、弧形侧抽芯机构。叙述了模具成形零件的设计与加工工艺过程、浇注系统和其它结构的设计过程,并介绍了模具工作过程。模具一次试模成功,运行灵活可靠,塑件精度达到了设计要求,外表光洁。 相似文献