共查询到18条相似文献,搜索用时 78 毫秒
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现有的汽车外覆盖件面畸变的检测和评价标准存在一定的局限性,难以满足理论研究和工程应用的要求。该文采用ABIS检测汽车外覆盖件的面畸变及测量面畸变的截面曲线,提出一种新的面畸变等级评价标准。结果表明,ABIS能够快速准确的检测面畸变及测量其截面曲线,以MATLAB软件计算出的评价指标Q作为汽车外覆盖件的面畸变评价标准,能够帮助汽车厂定量的评价面畸变等级。 相似文献
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汽车覆盖件面畸变评价指标研究 总被引:4,自引:1,他引:4
汽车覆盖件现有的面畸变评价指标均有一定的局限性 ,难以满足工程实践和理论研究多方面的要求。本文提出了一种新的面畸变评价指标 ,该指标既能反映零件上各点相对标准型面曲率变化程度的几何本质 ,又能比较客观地评价复杂零件局部畸变的水平。并用实例验证了二维和三维面畸变评价指标的正确性。 相似文献
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汽车覆盖件现有的面畸变评价指标均有一定的局限性,难以满足工程实践和理论研究的要求.本文分类统计了汽车覆盖件常见的面畸变分布及一般评价方法,提出了一种新的面畸变评价指标,该指标既能反映零件上各点相对标准型面曲率变化程度的几何本质,又能比较客观地评价复杂零件局部畸变的水平,并用试验验证面畸变评价指标的正确性. 相似文献
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汽车覆盖件成形中的面畸变及其工程控制 总被引:1,自引:0,他引:1
汽车覆盖件面畸变问题是影响其成形精度及表面质量的重要因素之一,其形成过程非常复杂并受多种因素的影响.通过汽车覆盖件面畸变问题的实物统计,对其形成机制进行了分析,讨论了面畸变问题研究的具体模型试验,结合工程实际提出了一些如何减小和消除面畸变的工艺控制措施. 相似文献
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汽车外覆盖件表面凹陷与畸变的实验与仿真 总被引:3,自引:0,他引:3
剧烈的市场竞争驱使汽车制造商从各方面设法提高其产品的质量。汽车外覆盖件的"A"级表面要求必须是光洁无瑕。可是由于制造过程的原因,在汽车外覆盖件的"A"级表面上还经常出现一些缺陷。在研究中,设计并制造了4种不同的实验模具,实验模具中包含了在汽车外覆盖件容易产生表面畸变的典型的反拉延特征。通过冲压实验,观察到表面缺陷的产生,并搜集产生表面缺陷处的应变及位移的历史数据,及在畸变区域的接触压力的数据。同时,还进行了冲压过程的数值模拟,模拟计算的结果与冲压实验的结果基本一致。通过冲压实验成功复制了在汽车外覆盖件上经常出现的表面缺陷,为进一步研究在汽车外覆盖件的"A"级表面上产生表面凹陷与畸变的根源奠定了基础。 相似文献
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目前商业冲压CAE分析软件对冲压开裂和起皱的预测精度达到90%以上,但是对回弹的预测精度仍然较低。在分析仿真软件不同设置条件对回弹精度的影响基础上,建立了适合覆盖件冲压回弹与面畸变CAE分析的设置规范。针对外覆盖件的回弹控制问题,提出了一种基于工程知识库与CAE分析相结合的回弹与面畸变控制方法。这种方法根据回弹仿真结果和经验数据库对外覆盖件冲压模面数据进行回弹补偿,补偿数据在满足仿真验证的基础上,面质量必须在Radius、Reflection和Section Analysis三个方面同原始数据一致。实践表明,此控制方法可以很好地预测和解决外覆盖件的回弹和面畸变问题。 相似文献
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Hongqing Shen Shuhui Li Guanlong Chen 《Journal of Materials Processing Technology》2012,212(7):1548-1556
A major problem with the evaluation of surface deflection is that panels are evaluated manually and to a great extent subjectivity is involved. For further study on surface deflections such as process optimization, it is necessary to evaluate the defect objectively and quantitatively. In this paper, quantitative analysis of surface deflections in the automobile exterior panel is carried out based on a curvature-deviation method. The curvature-deviation method uses the deviation-based indicators to quantify the surface deflection and uses the local curvature information to filter defect points in evaluation algorithm. In order to verify the effectiveness of the proposed evaluation method, sample panels with a door handle feature are stamped and measured in experiment. The sample panels are made of different materials and are formed under various blank holder forces. A stylus instrument is used to measure eight representative sections in the sample panel. The measurement result is analyzed in a program based on the curvature-deviation method. We also use the oil stoning method to make a subjective evaluation on surface deflection in the sample panel. By analyzing some verification curves and comparing the evaluation results based on the curvature-deviation method with the experimental oil stoning results, it is verified that the proposed curvature-deviation method can analyze the surface deflection accurately and has a good consistency with the stoning-based subjective evaluation method. In addition, the proposed method is applied to analyze the critical values of surface deflection and the influence of blank holder force on surface deflection. The proposed method to quantify surface deflections is beneficial to process optimization, material selection and tool design for automobile exterior panels. 相似文献
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There is no perfect evaluation criterion presently that can satisfy the needs of the engineering and the research on the surface deflection of automobile outer panels. A convenient 2D and 3D evaluation criterion that can quantitatively measure the magnitude and the location of surface deflection is developed mathematically. The surface deflection is shown by comparing the curvature variations between the pressed panel and the punch. The evaluation criterions tested by example are correct. The surface deflection is investigated through the experiment of the double-curved shallow shell drawing parts. The mechanism of surface deflection and the effects of forming conditions on surface deflection are analyzed. And the influence law of forming conditions on surface deflection is achieved, such as binder force, curvature radius (arc height of punch), sheet thickness, materials property and draw-beads. 相似文献
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以汽车覆盖件拉深工序为研究对象,利用有限元数值模拟方法,探讨了不同类型覆盖件拉深成形压料面的设计方法.结果表明:浅拉深覆盖件宜采用平压料面,能够降低拉深成形难度;深拉深覆盖件宜采用随形起伏压料面,可以保证各部分塑性变形均匀;质量要求不高的骨架类覆盖件,可将作为零件本身的翻边作为压料面的一部分. 相似文献