共查询到20条相似文献,搜索用时 31 毫秒
1.
倾斜板料冲裁的冲裁力研究 总被引:1,自引:0,他引:1
倾斜板料冲裁的冲裁力计算是一个尚待研究的课题。本文对倾斜板料圆孔冲裁的冲裁过程进行了探讨,将其分为板料包容冲头和板料不包容冲头两种类型和三个冲裁阶段,导出了每种类型各冲裁阶段冲裁力的计算公式,分析了冲裁力随行程的变化规律,研究了最大冲裁力和板料厚度、圆孔直径、板料倾斜角度的关系,获得了一些有价值的结论。 相似文献
2.
Thomas Pyttel Ralf John Michael Hoogen 《International Journal of Machine Tools and Manufacture》2000,40(14):1993-2002
Weight reduction is becoming increasingly important in engineering design. For this reason there is increased use of aluminium in different industries. High demands are placed on the technological process of sheet aluminium blanking. This paper presents results from a numerical model validated by experiment which illustrate the effects of some process parameters on blanking forces and edge quality. The blanking process is split into three different stages. An appropriate numerical model is necessary to describe the state of the sheet in each of these stages. The model for the blanking process presented in this paper is based on ideas of fracture mechanics. The validation of the numerical model with the results of associated experiments is an essential part of the presented approach. The combination of numerical simulation and physical testing results in a reduction of the necessary experimental effort. 相似文献
3.
A various number of products exist which require a clean-sheared edge due to function or surface feel. Traditionally, these
parts are produced on fine blanking presses with three separate and distinct movements. Shaving, in particular counter-shaving
is a shearing operation to improve the edge quality of a blanked part or punched hole. This paper introduces a progressive
die tool to realize the counter-shaving process on a single acting press. Advancing the chip flow through choosing a cutter
angle can achieve up to a 85% clean-sheared edge and rectangular edge. Thereby, a sharp-edged transition—without any rollover
depth—between the upper surface of the sheet metal and the sheared-edge are formed. The end of the clean-sheared edge is followed
by a tear which shapes a burr in the form of a triangular lappet, which can be deburred in a subsequent vibratory grinding
process. Experimental results of different process parameters for two sheet metal materials at three thicknesses are discussed
and compared to finite element calculations.
The presented research work was supported by the German Research Foundation (DFG). 相似文献
4.
由于超高强度钢板具有高强度、高韧性等特性,在冲切过程中对模具材料的磨损更严重,因此比较不同模具材料在冲切超高强度钢板时的抗磨损性能并选择合适的模具材料显得尤为重要。采用平行镶块组装形式的模具进行DP780超高强度钢板的冲切试验,并对不同冲切次数时3种模具材料(CALDIE、YXM1、SLD)对应的冲切试样的断面质量进行统计,以此分析模具材料的抗磨损性能。试验发现:冲切试样毛刺高度的变化能较好地反映出模具材料的磨损情况,冲切间隙的变化会影响试样断面剪切带宽度变化。CALDIE镶块在冲切试验的前期冲切试样质量最好,但后期其对应的冲切试样毛刺高度明显增加,说明CALDIE的稳定磨损期较短,这也降低了总的抗磨损性能。SLD镶块对应的冲切试样塌角高度、剪切带宽度及毛刺高度均是最大,说明其抗磨损性最差。综合比较发现,在冲切DP780板料时,SLD抗磨损性能最弱,CALDIE最好,YXM1介于两者之间。 相似文献
5.
6.
Up to 20% of all sheet metal produced is scrapped as blanking skeletons. A novel process is therefore designed and examined, aiming to transform tessellating ‘pre-blanks’ in-plane into the real blanks required for stamping. Prior to blanking, the sheet is formed with a set of ridged dies, from which pre-blanks are cut and then flattened into true blanks. Several different approaches to designing ridged dies are evaluated by simulation and experiment, and the best results demonstrate a potential reduction in blanking yield losses for can-making from 9.3% to 6.9%. 相似文献
7.
This paper provides a review and proposal for condition-based maintenance (CBM) in blanking of sheet metal. To date, little research on this topic can be found in literature, which is probably due to the complex nature of the process. Previous statistical, artificial intelligence (AI) and model-based approaches are analysed. Special attention is given to inherent assumptions and other sources of inaccuracy. In addition, it is demonstrated how the signature of the force–displacement relation changes significantly with increasing tool wear in a typical configuration of sheet steel blanking. An analysis follows as to how such behaviour could be used in CBM. A practical implementation of CBM in sheet metal blanking is proposed based on a hybrid solution. 相似文献
8.
通过分析液压机板料冲裁过程及缓冲技术,提出了自适应工况条件的几种冲裁缓冲调节装置,同时研制了缓冲作用点位置可精确调整和冲裁力能够自动跟踪的缓冲装置,较好地实现了减振和降噪功效,并成功地应用于冲裁落料液压机。同时,分析了不同结构装置的缓冲效果及应用现状,在实践生产中具有指导意义。 相似文献
9.
通过对金属板料无毛刺落料冲裁机理的研究,提出了一种负间隙落料的冲裁工艺,并设计了与其相对应的模具,讨论了无毛刺落料冲裁的工艺特征,使得无毛刺落料件在形位精度、尺寸精度和表面粗糙度等方面比普通落料件有极大的改善和提高。 相似文献
10.
基于零件冲裁毛刺高度的冲压模具磨损预测 总被引:1,自引:0,他引:1
冲压模具的磨损会引起冲裁间隙的增大,导致零件冲裁毛刺高度的增加。利用DEFORM-2D软件对0.8 mm料厚的CK75弹簧钢板料的冲裁过程进行有限元仿真,分析了冲裁模具的磨损过程,深入研究了冲裁工艺参数对冲裁毛刺高度与模具磨损的影响变化趋势。研究结果表明:在研究的冲裁工艺参数范围内,零件冲裁毛刺的高度随着冲裁间隙与冲裁速度的不断增加而增大,而随着模具刃口圆角半径的增大则表现出先增加后减小的变化规律;冲裁凸模的磨损深度伴随着冲裁间隙的增大而逐渐减小,随着冲裁速度的增加而增大,而随着模具刃口圆角半径的增加表现出先增大后减小的变化规律。此外,借助冲压模具进行冲裁试验,冲裁毛刺高度的仿真值与试验值之间的最大相对误差为17.7%,从而为衡量模具磨损状况提供了一种比较直接的方法。 相似文献
11.
板材剪切与冲裁加工实验的位移测量系统 总被引:1,自引:0,他引:1
针对板材剪切与冲裁加工的特点,设计了一种应变片式位移传感器。传感器可根据需要对量程进行调节,且相对精度不变,特别适于中小位移的测量。结合数据采集系统,在材料试验机上实现了板材剪切加工和精密冲裁实验的位移测量。 相似文献
12.
以冲压零件作为分析对象,基于响应曲面法设计板料冲裁的模拟试验,利用DEFORM-2D模拟软件对板料的冲裁变形过程进行有限元模拟,建立了冲裁工艺参数与冲裁断面光亮带长度之间的数学模型。通过模拟结果的分析得知:冲裁间隙与模具刃口圆角半径对光亮带长度的交互式影响最大。将冲裁速度、冲裁间隙以及模具刃口圆角半径作为设计变量,以光亮带长度作为优化目标,利用Design Expert软件对响应曲面模型进行优化,得到板料冲裁的优化参数:冲裁速度为14.04 mm·s-1,冲裁间隙为8.99%t(t为板料厚度),模具刃口圆角半径为1.25%t,光亮带长度的响应值为0.834 mm。此外,利用冲压模具进行试验验证,试验值与响应值之间的相对误差为11.8%,验证了响应曲面法应用于板料冲裁工艺参数优化的准确性。 相似文献
13.
14.
以C75S高强度弹簧钢作为研究对象,运用Deform-2D软件对板料冲裁过程进行数值仿真,基于响应面法对C75S弹簧钢的冲裁工艺参数进行优化。借助中心设计组合法设计冲裁试验,并建立了工艺参数与模具最大磨损深度之间的响应面模型,通过分析得知:模具刃口圆角半径与冲裁速度对凸模磨损的交互式影响最大;模具刃口圆角半径与冲裁间隙的交互式影响次之;冲裁速度与冲裁间隙的交互式影响最小。利用Design Expert软件得出最优的冲裁工艺方案为:模具刃口圆角半径为1.84t,冲裁速度为7.60 mm·s-1,冲裁间隙为13.23%t,凸模的磨损深度为4.02×10-6mm。此外,借助冲压模具进行冲裁试验,利用毛刺高度间接验证模具的磨损,试验值与响应面法优化值之间的相对误差为14.19%,两者保持较好的吻合性,从而为板料冲裁模具磨损的优化提供了一种有效方法。 相似文献
15.
基于知识的冲裁模CAD系统研究与开发 总被引:5,自引:3,他引:2
对基于知识的板料冲裁工艺与三维模具设计的智能化设计技术进行了系统研究,建立了基于知识的冲裁工艺与模具结构设计模型,研究了动态、柔性的工程设计接口在冲裁模设计系统中的实现。基于I-DEAS软件平台,利用二次开发和过程集成技术,开发了板料冲裁工艺与三维模具设计支持系统,有效提高了冲裁模设计的质量和效率。 相似文献
16.
In this paper, a blanking process of sheet metal is studied by the methods of numerical simulation and experimental observation. The effects of varying technological parameters related to the quality of products are investigated. An elastoplastic constitutive equation accounting for isotropic ductile damage is implemented into the finite element code ABAQUS with a user-defined material subroutine UMAT. The simulations of the damage evolution and ductile fracture in a sheet metal blanking process have been carried out by the FEM. In order to guarantee computation accuracy and avoid numerical divergence during large plastic deformation, a specified remeshing technique is successively applied when severe element distortion occurs. In the simulation, the evolutions of damage at different stage of the blanking process have been evaluated and the distributions of damage obtained from simulation are in proper agreement with the experimental results. 相似文献
17.
18.
以单层0.3 mm厚的薄铜板叠6层进行冲裁,研究冲裁间隙对多层薄铜板成形的影响。对多层薄铜板在冲裁成形中的受力与应力状态进行分析,利用ABAQUS软件对多层薄铜板在不同冲裁间隙下的冲裁质量进行有限元仿真。研究表明:冲裁初期最大等效应力出现在凸凹模刃口处,导致最上层与最下层薄铜板先行断裂,中间层薄铜板受相邻层挤压,最大等效应力出现在软质凸凹模刃口处,最后出现在中间层薄铜板缩紧截面内;随着冲裁间隙的增加,各层薄铜板拉伸变形明显,导致冲孔直径增大、毛刺高度增加。前3层薄铜板的冲孔直径变化较为稳定,与凸模直径接近;后3层薄铜板的冲孔直径变化幅度较大,与各自凹模直径接近。最后,通过试验验证,冲裁精度符合国标要求,在实际生产过程中选择合理的、尽可能小的冲裁间隙能提高冲裁件的冲裁质量。 相似文献
19.