星形套闭塞模锻光塑性模拟研究

利用光塑性方法以聚碳酸脂为模拟材料研究轿车等速万向节星形套闭塞模锻成形过程，获得星形套闭塞模锻成形过程的三维光塑性应变分布，提出其应变分布特征，并对典型截面应变进行计算分析，研究结果可实际钢质星形套闭塞模锻工艺和模具设计起一定的指导作用。     

等速万向节椭圆轨道设计与星形套有限元分析

文中阐述了球笼式等速万向节的结构和工作原理,根据球笼式等速万向节椭圆形轨道与钢球接触的共轭特性,建立了轨道与钢球接触的数学模型.该数学模型给出了球笼式万向节轨道设计的新方法.此方法适合油膜形成的沟底间隙作为设计参数,克服了常用万向节椭圆形轨道设计中曲率系数f的近似取值对啮合间隙的影响.同时,采用该设计方法给出了BJ型等速万向节椭圆轨道的设计参数,并利用三维造型软件Pro/E对BJ125型等速万向节星形套进行了三维建模,而且还采用有限元分析软件ANSYS分析了星形套的接触应力,验证了设计、选型的合理性,为万向节的设计和选型提供了新的思路和方法.     

球笼式等速万向节内部接触应力的有限元分析

通过三维重构技术建立轿车球笼式等速万向节的三维模型,并应用ANSYS软件对其承受极限转矩时的内部接触应力进行有限元分析,最后对比两种极限工况的数值解.结果表明,球笼式等速万向节内滚道接触应力大,易于磨损,疲劳寿命短.     

基于强度场的八球万向节内套结构与静强度设计匹配研究

为了对八沟道等速万向节内套进行结构和静强度设计,从钢球选型出发,对八沟道等速万向节内套进行了结构参数正向设计.对内套危险截面进行了全场静强度设计,以理想静强度场为目标,定量匹配了危险截面静强度的材料、热处理,并对全场静强度设计进行了定量评价.使用MTS静扭转试验机对等速万向节总成进行了静强度扭转试验,并用显微硬度计对内套进行了显微硬度试验以验证理论,结果表明按照基于强度场的机械结构和零部件的静强度设计与匹配方法设计的八沟道等速万向节星形套能够满足强度和功能需求.     

薄壁尖角零件的成形过程及性能的数值模拟

采用了DEFORM有限元分析软件对薄壁腔体台阶的成型过程进行了数值模拟,分析了冲压过程中失效形式产生的原因,并从改变工件结构、科学使用模具、热处理等几个方面提出了相应的改进措施,以提高模具寿命.     

雷达波导件塑性成形工艺分析及有限元数值模拟

以雷达上的波导件为研究对象,针对传统加工工艺的缺点以及工件形状特点,提出挤压成形工艺方案。利用有限元分析软件DEFORM对该工件的关键成形工序—反挤压过程进行刚塑性有限元数值模拟研究。通过数值模拟,观察到在不同压下测量时毛坯的等效应力、等效应变云图及挤压力与行程图,得到其金属流动规律,为合理设计模具和验证工艺提供依据。     

雷达波导件塑性成形工艺分析及有限元数值模拟

本文以雷达上的波导件为研究对象，针对传统加工工艺的缺点以及工件的形状特点，提出挤压成形工艺方案。利用有限元分析软件DEFORM对该工件的关键成形工序——反挤压过程进行刚塑性有限元数值模拟研究。通过数值模拟，观察在不同压下量时毛坯的等效应力、等效应变云图及挤压力与行程图，得到金属流动规律，为合理设计模具和难工艺提供依据。     

BJ型等速万向节应力计算与结构设计

计算了球笼等速万向的接触应力，确定了球笼等速万向节的钢球直径，并用实例说明了钟形壳、星形套和保持架的尺寸设计过程。     

七沟道球笼式等速万向节受力及仿真分析

基于球笼式等速万向节钢球的受力模型,推导了一个钢球在星形套内沟道和钟形壳外沟道内运动时,沟道对钢球的周向力、沟道对钢球的法向接触力、保持架窗口对钢球的法向接触力的表达式。在此基础上,基于Herzt接触理论,对上述受力进行了Adams动力学验证。结果表明:仿真结果和理论计算基本吻合,七沟道球笼式等速万向节的周向力、法向接触力、钢球与星形套的摩擦力、与保持架的摩擦力均小于六沟道,并且随着摆角的变化而变化。     

VW-1—011型球笼式万向节保持架有限元分析

VW-1-011型球笼式万向节广泛应用于轿车行业,其保持架是约束钢球运动的中间环节,由于在实际生产中钟形壳的偏心距和星形套的偏心距不可能完全相等,造成保持架受冲击力作用而破坏.针对这一问题利用大型有限元ALGOR软件对保持架处于不同关键位置进行了有限元分析,得到了其应力应变分布,分析出保持架结构薄弱部位并进行比较式优化改进,可为球笼式万向节保持架设计者提供一定的依据.     

万向节星形套磨削加工中存在问题与改进

国产球笼式等速万向节由于回转方向间隙原因会产生很大的噪声和振动,其中星形套是球笼式等速万向节至关重要的零件,提高星形套制造精度的关键在于提高星形套零件沟道的加工精度,在机床的精度不变情况下,必须设计研制合理卡具,才可以获得稳定的加工精度,提高生产率和降低加工成本。     

密封套强力旋压成型工艺仿真过程研究

采用 simufact有限元软件进行数值计算,研究了某密封套的旋压成型工艺过程,得到了旋压过程中等效塑性应变及等效应力分布规律,分析了进给比对筒形件成型精度及旋压力的影响,即密封套旋压成型中间进程的等效塑性应变最大,进给比在一定范围内增大,壁厚偏差变大,成型质量变差。     

丝杠冷滚打变形力影响因素研究

为研究丝杠冷滚打成形过程中滚打轮半径、滚打轮圆角半径和打入量与变形力之间的关系,在丝杠冷滚打成形原理的基础上建立了有限元仿真模型。通过仿真获得单次滚打以及多次滚打成形过程中,变形力随滚打轮半径、滚打轮圆角半径和打入量的变化规律;设计了正交试验,研究打入量、滚打轴转速、滚打轮厚度及工件转速4个因素对变形力的影响规律。在自行设计的冷滚打成形丝杠设备上进行实验,测得变形力的变化趋势与仿真结果基本一致,验证了有限元仿真模型的正确性。     

外凸台内齿圈件成形过程数值模拟效率影响因素正交试验分析

采用刚黏塑性有限元法对外凸台内齿圈件精密成形过程进行了数值模拟,通过正交试验法研究了各因素对成形力的影响,找到了影响数值模拟效率的规律,研究结果有利于成形工艺的优化设计,指导企业生产。     

Analysis and design of flat-die hot extrusion process 1. Three-dimensional finite element analysis

Non-steady-state-coupled three-dimensional analysis is required for investigating complex material flow in practical flat-die hot extrusion processes of aluminum alloys in various channel sections. It is important since the material flow behavior actually determines the amount of distortion of the extruded product. Thus, a non-steady thermo-rigid-viscoplastic finite element program was developed for numerical simulations of the process. Since severely deforming elements of the workpiece can easily interfere with the sharp edges of the flat-die, an automatic remeshing module based on a simple section-sweeping scheme and new contact algorithm were incorporated to allow continuous simulation without manual intervention with less volume loss and computation time. With developed finite element program, non-steady finite element analyses of extrusion processes were carried out for two types of channel-section with constant bearing length of 5 mm. From simulation results, it was found that the exit velocity of the workpiece varied depending on the cross-sectional thickness of the exit and the amount of deflection of the workpiece was not greatly affected by variations of either the workpiece temperature or punch velocity under the present simulation conditions.     

Analytical modeling and numerical simulation for three-roll bending forming of sheet metal

The three-roll bending forming of sheet metal is an important and flexible manufacturing process due to simple configuration. It is suitable for forming large sheet parts with complex, curved faces. Most researches on roll bending forming of large workpiece are mainly based on experiments and explain the process through macroscopic metal deformation. An analytical model and ABAQUS finite element model (FEM) are proposed in this paper for investigating the three-roll bending forming process. A reasonably accurate relationship between the downward inner roller displacement and the desired springback radius (unloaded curvature radius) of the bent plate is yielded by both analytical and finite element approaches, which all agree well with experiments. Then, the three-roll bending forming process of a semi-circle-shaped workpiece with 3,105 mm (length)?×?714 mm (width)?×?545 mm (height) is simulated with FEM established by the optimum tool and process parameters. Manifested by the experiment for three-roll bending forming of this workpiece, the numerical simulation method proposed yields satisfactory performance in tool and process parameters optimization and workpiece forming. It can be taken as a valuable mathematical tool used for three-roll bending forming of large area sheet metal.     

叶片精锻过程数值模拟结果动态彩色云图的实现方法

对有限元数值模拟结果进行可视化处理,可提高数值模拟结果检查、分析的效率和直观性。彩色云图是实现模拟结果可视化的主要手段之一。本文以叶片精锻过程为例,研究了其精锻过程彩色云图及其动态显示的生成原理和实现过程,结果表明,该方法简洁、精确、便于实际运用。     

基于LS-DYNA的电子元件冲压成形仿真研究

针对电子元件结构尺寸较小,采用传统方法设计其成形模具效率低且很难保证质量,基于LS-DYNA接触碰撞算法,建立了工件、凸凹模的冲压成形有限元模型,定义了成形条件。在分析过程中通过创建接触界面来实现凸凹模与工件之间力和运动的传递。分析得到了工件应力应变分布图和成形性能图。采用接触碰撞算法可根据节点的时间-位移图来判断工件成形质量,并通过调整分析输入参数来获得最佳成形条件:凸凹模间隙和冲压速度。将仿真分析结果应用到模具设计和冲压工艺参数的拟订定中,实际生产表明仿真分析数据合理可靠。     

基于DEFORM-3D的外凸台内齿圈件正交试验法工艺优化研究

采用刚粘塑性有限元法对外凸台内齿圈件精密成形过程进行了数值模拟,得出了成形过程中成形力规律,列出了影响成形力的两个因素:温度和凸模速度.通过正交试验法研究了各因素对成形力的影响,找到了最佳组合.研究结果有利于成形工艺的优化设计.     

Optimal geometric tolerance design framework for rigid parts with assembly function requirements using evolutionary algorithms

A new forming technology of car steering knuckle was presented, aiming at eliminating the defects in the existing steering knuckle forming process. Based on orthogonal experimental design to numerical simulation by using FEM, for steering knuckle closed extrusion of multi-objective optimal design problems in systematic research, the influences of extrusion temperature and speed, mold temperature, and lubrication of forming technology were discussed with comprehensive scoring method and integrated balance method, then the process parameters used in the forming were applied in the productive practice. Results show that the orthogonal test method combined with finite element simulation can be flexible and efficient in handling of multi-objective optimization problems. As for the forming of other types of long rod fork forging, the new process and the design method have important guiding significance.