汽车覆盖件成形数值模拟与模具型面设计

以某汽车覆盖件为研究对象,利用板料分析软件Autoform对其进行了冲压方向的确定、压料面和工艺补充面设计、拉延筋设计以及拉延成形过程的数值模拟。通过仿真预测了板料成形过程中拉裂、减薄、起皱等缺陷,并根据模拟结果分析了板料与凸凹模的摩擦、工艺补充面、压边力、拉延筋等因素对缺陷产生的影响,进而调整优化了板料成形工艺参数和模具型面结构,消除了零件成形中的质量缺陷,提高了成形工艺的可靠性,为实际生产中覆盖件冲压工艺确定和模具型面设计提供了参考和依据。     

基于Autoform的汽车左右护板的冲压成形有限元分析

介绍了汽车覆盖件冲压成形仿真的研究背景,论述了板料冲压成形有限元模拟的理论和主要步骤。采用Autoform软件对汽车左、右护板零件进行了冲压成形过程的有限元分析,完成了左右对称零件在Autoform软件中的模拟参数优化,预测了板料成形过程中减薄、拉裂、起皱等缺陷,同时分析缺陷产生的原因;通过调整拉深筋参数与压边力大小,对成形结果进行优化,证明了有限元模拟分析设计方法具有实用性。     

基于Autoform轮毂成形工艺分析与模具设计

以汽车轮毂为研究对象,利用有限元分析软件Autoform对轮毂成形性进行分析,在板料成形分析过程中,对板料减薄率分布、成形极限图、应变分布、拉深筋设置等分析是为模具设计提供技术支持,依据Autoform软件仿真结果,确定了轮毂的冲压成形工艺方案,并设计相应的模具结构。     

基于Autoform的汽车覆盖件成形有限元分析

论述了板料冲压成形有限元模拟的理论和主要步骤。采用Autoform中的增量计算法与双动拉延对汽车覆盖件进行了冲压成形过程的有限元分析,预测了板料成形过程中减薄、拉裂、起皱等缺陷,同时分析缺陷产生的原因;通过调整拉深筋参数与压边力大小,对成形结果进行优化,证明了有限元模拟分析设计方法具有实用性。     

基于Autoform右背门里板拉伸起皱问题的调试处理

对汽车右背门里板拉伸模在调试中出现的制件起皱问题进行了分析,并采取了相应的对策。重点介绍了利用Autoform软件的板料成形模拟方法指导调试制件起皱缺陷及调整拉伸模的过程。通过缺陷预测来制定缺陷预防措施,经过不断改进,制件外观质量、形状及尺寸精度都达到了要求,对今后类似制件起皱问题的解决有一定的参考作用。     

基于Autoform的轿车引擎盖板冲压成形的仿真

采用Autoform中的增量计算法与双动拉延,对轿车引擎盖零件进行了冲压成形过程的仿真,预测了板料成形过程中减薄、拉裂和起皱等缺陷,同时分析了缺陷产生的原因。证明了仿真设计方法具有实用性;通过反复模拟,找出了合理的工艺参数。     

基于Autoform软件的冲压工艺参数稳健性设计

先利用正交表对冲压速度、凹模圆角、摩擦系数、板料厚度和压边力大小等5个因素进行试验设计,再采用Autoform软件对冲压件成形过程中进行模拟分析,研究了各种因素对零件最终成形结果的影响。通过Minitab软件对各参数进行分析,利用稳健性设计原理,找出最佳方案再进行模拟分析得到最佳结果。     

汽车轮侧内板冲压工艺仿真与试验

以某一汽车轮侧内板为研究对象,研究其成形所需工艺,并使用Autoform软件进行仿真建模,对其成形过程进行模拟分析。分析了各工艺参数对汽车轮侧内板零件成形的影响,预测了板料成形过程中可能存在的起皱、拉裂和成形不足等缺陷,通过将压边力从300 k N增大到800 k N,并将拉延筋系数由0.6减小到0.5等设置,消除了成形过程中的起皱和拉裂等缺陷,零件表面质量控制在合格要求之内。最后按软件仿真进行实冲试验,所得零件和仿真结果基本一致,证明了仿真结果的准确性。利用优化后的方法,零件已批量生产,大大节省了试模成本和时间。     

基于Autoform的铝合金引擎盖成形模拟及优化

基于板料成形数值模拟软件Autoform,采用轻量化铝合金成形某车型引擎盖外板,并进行模拟及优化,以成形极限图、减薄率等为优化目标,对相关工艺参数进行调整,优化成形工艺参数与模面形状,可为相关企业的铝合金引擎盖生产提供参考,推进铝合金外覆盖件在汽车轻量化中的应用。     

基于工艺切口优化设计的汽车尾门内板拉深成形研究

针对某车型尾门内板在拉深成形过程中出现的起皱与开裂缺陷,介绍了其产生原因,提出了优化拉深筋参数以加大进料阻力的解决方法,并采用Autoform模拟软件准确预测制件成形缺陷,指导拉深模工艺切口的布局优化,改善局部板料的流动。生产实践表明,基于工艺切口的优化设计可有效控制制件起皱与开裂,可为类似汽车覆盖件冲模设计与冲压工艺提供参考。     

基于Dynaform对电视机后盖成形的数值模拟研究

利用Dynaform板料成形分析软件可以模拟板料在成形过程中出现的褶皱、翘曲和拉裂等各种问题,以影响电视机后盖成形最大的压边力、材料为参数进行试验,调整不同参数值和材料,以得到最佳优化成形方案,提高生产率,节约成本的目的。     

1100-H14铝合金板冷冲锻成形过程的有限元模拟

金属板材冷冲锻成形是近年来发展起来的复合成形新技术,其特点是板材冲锻时不但完成零件形状的成形,还兼有局部结构的体积成形,如凸柱成形.针对带有凸柱的散热板基座,通过对1100-H14铝合金板材冷冲锻成形有限元模拟,探讨坯料厚度、坯料形状、摩擦因数及模具结构对凸柱成形的影响规律.结果表明:坯料越厚,越有利于凸柱成形;摩擦因数越大,越有利于凸柱成形;圆形坯料形状及带有背压的模具结构有利于凸柱成形.模拟结果与实验结果吻合.     

Investigation on formability enhancement of 5A06 aluminium sheet by impact hydroforming

High strain rate (HSR) forming has been found to be able to enhance the formability of sheet metals like electro-magnetic forming. Impact hydroforming (IHF) is proposed, in which the sheet is formed with high-pressure pulse combining hydroforming and HSR forming. An IHF bulge test setup was designed, 5A06 aluminium sheet was tested with strain rate of 2 × 10³ s^?1 showing remarkable thickness strain increase compared with quasi-static condition. A new IHF equipment is designed, the IHF process was verified effective with the equipment, complicated aluminium aircraft sheet part with high drawing ratio was formed that cannot be formed with quasi-static hydroforming.     

Analysis of Residual Stresses in High-Pressure Sheet Metal Forming

The further development of innovative forming processes like sheet metal hydroforming is only possible with the help of detailed knowledge about the workpiece properties and their formation depending on the particular process strategy. Up to now, the detailed understanding regarding the formation of residual stresses in hydroforming processes like the high-pressure sheet metal forming (HBU) is insufficient. Therefore, numerical (FEM) and experimental investigations on the residual stresses induced in HBU-formed workpieces have been carried out. The results show that a higher fluid pressure leads to significantly lower residual stresses in addition to an improved accuracy of form and dimensions.     

变截面板方盒形件成形参数的正交试验分析

以影响变截面板方盒形件成形的板料厚度比、板料形状与尺寸、压边力及凹模圆角半径等为参数,以成形深度和过渡区移动量为考核目标,通过数值模拟和利用正交优化方法对比分析不同方案下成形深度、过渡区移动量,调整危险点应变路径,确定最优方案,可提高变截面板成形性能。     

Textured surfaces for deep drawing tools by rolling

In this paper, macroscopic textured tool surfaces manufactured by rolling are investigated. Focus is on selective adjustment of friction by local texturing of tool areas to influence the material flow during deep drawing operations. Flat strip drawing tests were performed using friction elements with open textures. The texturing influences the friction conditions and affects the material properties of the stripes. The use of these surfaces results in a significant increase in friction, which allows an additional control of the material flow during sheet drawing operations. The main mechanisms for increased drawing forces are elastic deformation near the area of the texture and local plastic deformation on the sheet surface. Using strips made of mild steel, the texturing leads to an increased roughness of the sheet metal surface and, in the case of high surface pressure, to plastic deformations of the strips. Compared to conventional measures like draw beads, rolled-textured surfaces allow to retard the material flow during sheet drawing operation without excessive strain hardening in the sheet material.     

Comparison of alternative approaches of single point incremental forming processes

Incremental sheet metal forming is becoming an attractive technology for fast prototyping and small batch production of sheet metal parts. The majority of investigations are focused on the use of a rigid tool to incrementally form the sheet metal into a final shape. An interesting alternative is to substitute the rigid tool with a high velocity water jet (WJ). The comparison between using a rigid tool and a WJ shows that each method has its advantages and disadvantages. This investigation is aimed to identify the most influential parameters affecting the forming process through experimental comparison of the two observed methods. Technological windows based on non-dimensional values and relevant process parameters like force on the rigid tool and water pressure were defined.     

1420合金板材氧化膜对氩弧焊缝中气孔的影响

通过X射线透视和金相方法相结合，观察了1420合金板材氩弧焊缝中气孔的大小、数量及分布，发现气孔在焊缝两侧熔合线附近呈链状分布，且主要分布在焊缝根部和背面余高中。试验研究表明焊缝中气孔主要来源于接头背面的氧化膜。同时分析了气孔的形成机理与分布原因。气孔的气相主要由H2、CO2、CO、H2O等组成。通过对断口上气孔形貌分析可将气孔形貌分析可将气孔按形状分为五大类，即球形、喇叭口形、豆荚形、不规则形和陷洞形。     

Pneumatic Bulging of Magnesium AZ 31 Sheet Metals at Elevated Temperatures

This paper deals with forming magnesium sheet metal components like auto body parts by pneumatic bulging. Furthermore, this paper deals with the evaluation of true stress-true strain curves as well as with forming limit curves determined by pneumatic bulging at temperatures up to 350°C. It can be shown that magnesium AZ31 is quite good formable at temperatures in the range of 250°C to 350°C.Outgoing from these fundamental investigations, an auto body sheet metal component was formed by pneumatic bulging at a temperature of about 300°C.Furthermore, the strains over the component were measured with an automated grid analysis. This analysis shows a nearly equal distribution of the strains over the component.     

Process layout avoiding reverse drawing wrinkles in hydroforming of sheet metal

Sheet metal forming processes like the fluid form process or hydromechanical deep drawing have the potential for the manufacture of parts having high precision, large drawing ratio, and low costs especially for small and medium lot sizes. In deep drawing using a separating membrane between the liquid and the sheet the process layout for drawing of complex parts must avoid not only the typical failures of bottom fracture, first and second order wrinkles, but also an additional type of wrinkles which are maybe created at the beginning of the process. The development of these wrinkles is described using an analytical model, which was validated by experimental results. The model was used to develop the process layout for deep drawing of a complex sheet metal part.