基于均匀设计方法的热板研究

光刻工艺中对热板表面的温度场均匀性有着极高的要求。在热板设计参数的选择问题上,通过使用均匀实验设计的方法,从均匀分散性的角度出发挑选代表点,并对这些代表点应用ANSYS仿真模拟软件进行分析,得到不同设计参数情况下的热板表面温度场均匀性数据。然后对代表点的仿真结果数据进行回归建模。经过验证,回归模型计算结果与仿真结果有较高的一致性。根据所得到的回归模型,热板设计人员可以方便的了解不同设计参数取值情况下的热板表面温度的均匀性,并更好的做出选择。     

Fatigue analysis-based numerical design of stamping tools made of cast iron

This work concerns stress and fatigue analysis of stamping tools made of cast iron with an essentially pearlitic matrix and containing foundry defects. Our approach consists at first, in coupling the stamping numerical processing simulations and structure analysis in order to improve the tool stiffness geometry for minimizing the stress state and optimizing their fatigue lifetime. The method consists in simulating the stamping process by considering the tool as a perfect rigid body. The estimated contact pressure is then used as boundary condition for FEM structure loading analysis of the tool. The result of this analysis is compared with the critical stress limit depending on the automotive model. The acceptance of this test allows calculating the fatigue lifetime of the critical zone by using the S–N curve of corresponding load ratio. If the prescribed tool life requirements are not satisfied, then the critical region of the tool is redesigned and the whole simulation procedures are reactivated. This method is applied for a cast iron EN-GJS-600-3. The stress-failure (S–N) curves for this material is determined at room temperature under push pull loading with different load ratios R?=?σ _min/σ _max?=??2, R?=??1 and R?=?0.1. The effects of the foundry defects are determined by SEM observations of crack initiation sites. Their presence in tested specimens is associated with a reduction of fatigue lifetime by a factor of 2. However, the effect of the load ratio is more important.     

A knowledge-based blackboard framework for stamping process planning in progressive die design

It is widely accepted that stamping process planning for the strip layout is a key task in progressive die design. However, stamping process planning is more of an art rather than a science. This is in spite of recent advances in the field of artificial intelligence, which have achieved a lot of success in incorporating built-in intelligence and applying diverse knowledge to solving this kind of problem. The main difficulty is that existing knowledge-based expert systems for stamping process planning lack a proper architecture for organizing heterogeneous knowledge sources (KSs) in a cooperative decision making environment. This paper presents a knowledge-based blackboard framework for stamping process planning. The proposed approach speeds up the progressive die design process by automating the strip layout design. An example is included to show the effectiveness of the proposed approach.     

CBR在冲压工艺设计系统中应用分析

由于冲压产品随着轻工、汽车、电子等行业发展而用量日趋增大,冲压模具行业成为现代制造业的重要组成部分。考虑到在设计过程中相似的冲压件会存在相似的冲压工艺的特点,Case Based Reasoning(CBR)将会在冲压工艺设计中显示出独特的优势,本文在分析CBR的冲压工艺设计系统的架构基础上,设计冲压工艺设计系统,并对其进行实例详细分析,对于冲压模具发展具有一定帮助。     

Cooling system of hot stamping of quenchable steel BR1500HS: optimization and manufacturing methods

The innovative hot stamping press of quenchable steel mainly includes two stages: hot forming of blank at elevated temperature and quenching of hot stamped part in closed water-cooled tools. Crucial stage in hot stamping process is quenching of hot formed part in water-cooled tool to achieve final high ultimate tensile strength. In quenching stage, cooling rate of hot stamped part has a significant effect on final mechanical properties of hot stamped part. Hence, in this paper, a new method is proposed to optimize cooling system to improve effectiveness of quenching and thus final mechanical properties of hot stamped part. In this method, cooling channel is introduced in tools, and hot stamping experiments are combined with corresponding finite element numerical simulations to optimize cooling system. According to cooling system optimization, two different sets of tools used to manufacture square-box-shaped part and B pillar of automobile are manufactured using drilling method and pre-embedding method, respectively. Hot stamping experiments and corresponding simulations are performed to verify the effectiveness of optimized cooling system.     

基于CAE的某加强件冲压成形工艺分析与方案的确定

通过CAE的平台,对某典型汽车内覆盖加强件的冲压成形工艺方案研究,得出了一般大型板料冲压成形方案制定的方法.由于首工序成形体现整个成形工艺方案思路,它是整个工艺方案的核心.考虑到装配、制件表面质量、加工成本等因素,重点论述了如何借助CAE平台实现对冲压工艺方案的可行性评估,从而在多个成形工艺方案中选择一条优化的工艺路线.     

汽车引擎盖内板冲压工艺设计及数值分析

针对复杂的汽车引擎盖内板在冲压成形中容易产生破裂缺陷的问题,利用AutoForm有限元软件对引擎盖内板进行工艺设计以及数值分析.将正交试验设计方法与冲压数值分析相结合,探讨冲压方向、压边力、拉深筋圆角半径、拉深筋深度和摩擦因数对汽车引擎盖内板冲压成形质量的影响,并利用直观分析法,确定最优工艺参数组合,最终达到理想效果.     

基于FLUENT的热压板通道布置设计优化

用有限元仿真元件FLUENT分析热压板的温度场分布情况,找出影响温度分布的原因及参数,并根据仿真结果改变通道布局及调整通道间距以提高热压板温度均匀性,减小工作面温差,提高产品质量。     

Tribological performances of Zn-based coating in direct hot stamping

In hot stamping of High Strength Steels, the severe tribological conditions make the metal sheet coating one of the most critical choices for the technical and economical success of the process. This paper presents the approach and the results in evaluating a Zinc-based coating applied to boron steel sheets in hot stamping operations. Thermal and physical-simulation experiments were carried out to evaluate the chemical interactions between the coating and the metal sheet and the tribological performances during the process. The coating proved to overcome most of the drawbacks of the currently utilized Al–Si coating.     

Research of knowledge-based system for stamping process planning

This paper gives a brief introduction to establishing a knowledge-based system for intelligent stamping process planning. Studies on the system’s framework, knowledge model and reasoning mode are introduced. Some key technologies such as the feasibility of the stamping process, an optimal algorithm for blank layout, intelligent strip layout and force calculation are researched. The efficiency of stamping process planning can be improved by the system.     

数控机床主轴部件动态优化设计

在对某型数控车床进行空运转、切削及模态试验的基础上，确定了机床主轴部件动刚度薄弱是引起机床切削的结构颤振方面的原因。据此，建立了机床主轴部件的有限元动力学模型，并对主轴部件进行了静、动特性的计算和动态优化设计。     

数据接口零件冲压工艺及模具设计研究

针对数据接口冲压零件批量大、尺寸小,尺寸精度和形位公差要求高的特点,设计了合理的排样图及模具结构图,分析了冲压生产该零件可能产生带料扭曲、带料扇形变形和零件间间距不均等缺陷的原因,并找到了相应的解决措施。     

电器支架冲压工艺及模具设计研究

针对电器支架批量大、尺寸小、尺寸和形位公差要求高的情况,设计合理的排样图及模具结构,分析冲压生产该支架可能产生的带料扭曲变形、2-φ1.6 ±0.05mm孔位置尺寸精度难以保证,以及冲裁不完全或断面重复冲裁等缺陷的产生原因,并找到了相应的解决措施.     

A comparison study on wear characteristics of Ni-based,Co-based and Fe-based alloys for heated hot stamping tools manufactured by surfacing technology

The International Journal of Advanced Manufacturing Technology - To meet the demanding requirement of ultra-high-strength steel parts with tailored properties, heated hot stamping tools are...