基于知识的钣金冲模凸模与凹模快速设计研究与开发

传统钣金冲模的凸、凹模设计以几何形状作为操作对象,效率低且很少融入模具设计知识和设计经验,限制了模具的快速设计,为此提出了钣金冲模的凸、凹模快速设计方法,该方法以模具设计规则为基础,归纳了冲模设计过程中各种典型凸模和凹模设计样式,结合知识工程的基本思想,实现了基于知识的凸、凹模设计,并具有凸、凹模的快速互换功能,并可对凸模自动进行强度和刚度校核。     

基于RE技术的冲压件的模型重建

通过一冲压件实物,从3D数据采集谈起,贯穿整个CAD模型重建、分析过程,介绍了Geomagic软件、Imageware软件和UG软件在逆向建模中的特点及过程中存在的问题及解决方法。     

Improvement in formability by control of temperature in hot stamping of ultra-high strength steel parts

The formability in hot stamping of an ultra-high strength steel part was improved by preventing a temperature drop of the flange increasing resistance to drawing. The temperature drop was reduced by high speed forming using a servo press and by less contact with a die and blankholder using spacers thicker than the sheet. In addition, hardening of the flange was prevented by slow cooling for the less contact using the spacers to facilitate trimming of the hot-stamped part. From a hot deep drawing experiment with a hemispherical punch, the effectiveness of the present approaches of temperature control was demonstrated.     

铍板材深冲压成形异形件探讨

冲压成形是金属板材加工异形件的最基本方式。金属材质不同,冲压成形异形件的难易程度不同,主要影响因素是冲压成形性能和冲压成形极限。文章结合铍板材的冲压成形性能和冲压成形极限,对铍板材冲压成形异形件的难易性作了探讨。     

回火时间对1800 MPa级热成形钢组织和性能的影响

采用扫描电镜、电子背散射衍射技术、室温拉伸试验等研究了1800 MPa级热成形钢经930 ℃保温4 min保压淬火后在200 ℃回火不同时间(10~30 min)对其组织和力学性能的影响。结果表明,随着回火时间的延长,试验钢的抗拉强度变化较小,其屈服强度和断后伸长率均呈先增后减的趋势。经20 min回火后,马氏体亚晶粒尺寸最小;回火10 min后,组织中的小角度晶界最多。200 ℃回火10 min后由于试验钢的残余应力释放、马氏体亚晶粒尺寸减小和小角度晶界增多,综合影响下热成形钢的综合力学性能最佳,其抗拉强度为1844 MPa,断后伸长率从淬火态的8.27%提升到11.78%,强塑积达21 GPa·%以上,说明短时回火有利于该超高强度钢的综合性能提高及其热成形件的可靠应用。     

轴承架的冷冲压拉深工艺及模具设计

从企业的生产需求出发,对轴承架进行冲压工艺分析。对生产加工零件的冲压模具和拉深模具进行整体设计,使设计的产品能够实际加工生产。在生产中经过检验,设计最终解决了企业的难题。     

Analysis of manufacturing effects on fatigue failure of an automotive component using finite element methods

In this study, the fatigue life of an automotive suspension component was analysed using finite element methods with regard to stamping and welding effects. Because automotive suspension components are produced by forming and welding sheet metal, there are various effects on the final product, such as uneven thickness distribution, residual stresses and weld notches. Manufacturing effects may change the mechanical performance of the automotive components; therefore, it is desirable to consider these effects in the early design stage. Residual stresses due to work hardening and thermal deformation were investigated through process simulation. The redistribution and relaxation of residual stresses in a component were investigated in fatigue life analysis under a cyclic loading condition. Various equivalent relaxation curves were investigated and one was selected after comparisons with test results. The fatigue simulation results were compared to the test results; a good correlation between the two was achieved for the residual stress effects in terms of life cycles and failure locations. The simulation results also show that welding produces more detrimental effects than stamping with regard to the fatigue life of a component.     

气缸在冲压模具行业的应用

重点介绍气缸在汽车冲压模具行业的开发和应用,以及如何在模具结构设计中使用气缸,使用方法及注意事项。     

Investigation on induction heating for hot stamping of boron alloyed steels

Within hot stamping of quenchenable steels the blank is heated up to austenitization temperature, transferred to the tool, formed rapidly and quenched in the cooled tool. Essential for the complete process is the heating of the blank which is currently carried out with roller hearth furnaces. As a consequence of rising energy costs new and more time and energy effective heating systems are needed. The paper presents investigations on induction heating as an alternative heating technology. Results concerning the process windows as well as material characteristics and grain structure will be presented and discussed.     

辅助几何特征在车身冲模数控加工中的应用研究

为提高数控加工程序编制质量及效率,基于数控程序编制流程分析了其工作要点,在此基础上,结合实例分类研究了辅助几何特征在车身冲模型面及结构面数控程序编制中的构造与引用问题。结果表明,车身冲模数控程序编制中需要构造与引用的辅助几何特征主要是片体模型与加工边界;片体模型一般基于工序件构造,加工边界则参考相关特征创建;辅助几何特征的构造与引用能显著提高编程质量及效率;所述实例经实践检验是可行的。