共查询到20条相似文献,搜索用时 656 毫秒
1.
2.
Li-Ping Lei Jeong Kim Beom-Soo Kang 《International Journal of Machine Tools and Manufacture》2000,40(12):1691-1708
An FEM program, HydroFORM-3D, for the analysis and design of tube hydroforming processes, has been developed by modifying and adding some subroutines to the previous rigid-plastic finite element program, and then applied to the hydroforming process for an automobile rear axle housing. This paper includes the theoretical background of the program development. Through a numerical simulation, an optimum process is proposed to meet the practical requirements, which shows the efficiency of the numerical simulation. Two types of hydroforming dies are analyzed by numerical simulation. The sliding-type die has the drawback of a possibility of buckling, whereas the fixed-type die causes bursting failure. The thickness distribution of the final product is affected not only by the types of die, but also by the loading paths. The potential failure site for rear axle housing predicted by the numerical simulation is consistent with the experimental results. The values of maximum axial compression force for the first and second hydroforming processes are also in good agreement with experimental data. To manufacture a sound automobile rear axle housing without failure, it is better to use the sliding-type die and it is also critical to maintain a suitable hydraulic pressure level. 相似文献
3.
黎永杰 《锻压装备与制造技术》2011,46(3)
对复杂形状空心构件内高压成形工艺进行了数字模拟研究。采用有限元模拟,对矩形截面空心零件弯曲部位在内高压成形过程中产生起皱、破裂等缺陷进行了分析;针对矩形截面空心件弯曲部位,提出采用椭圆截面充液预成形的方法,控制起皱、破裂缺陷的产生,成形质量较理想。并通过试验进行了验证,采用较低压力可以改善内高压成形过程中材料的分布、提高材料的成形极限、控制缺陷产生并提高产品质量。 相似文献
4.
5.
Kai Jin Qun Guo Jie Tao Xun-zhong Guo 《Journal of Materials Engineering and Performance》2017,26(11):5188-5196
Numerical simulations of tube hydroforming process of hollow crankshafts were conducted by using finite element analysis method. Moreover, the modified model involving the integration of isotropic–kinematic hardening model with ductile criteria model was used to more accurately optimize the process parameters such as internal pressure, feed distance and friction coefficient. Subsequently, hydroforming experiments were performed based on the simulation results. The comparison between experimental and simulation results indicated that the prediction of tube deformation, crack and wrinkle was quite accurate for the tube hydroforming process. Finally, hollow crankshafts with high thickness uniformity were obtained and the thickness distribution between numerical and experimental results was well consistent. 相似文献
6.
7.
Use of FEM in the metal forming process has been a proven analysis tool. Two-dimensional FEA for simplified sections can help to reduce time and cost in part, tooling and process design in tube hydroforming technology as it is a relatively new process, and the existing experience and knowledge base is not as broad as with other forming processes. Some case studies are presented to demonstrate the use of two-dimensional FEA in the hydroforming process. Upon verification through comparison of FEA predictions with experimental results, further planned simulations are conducted to generate simple design rules on geometrical and process parameters. 相似文献
8.
9.
10.
Seyed Jalal Hashemi Hassan Moslemi Naeini Gholamhosein Liaghat Roohollah Azizi Tafti Farzad Rahmani 《Journal of Materials Engineering and Performance》2013,22(1):57-63
Reduction of weight and increase of corrosion resistance are among the advantageous applications of aluminum alloys in automotive industry. Producing complicated components with several parts as a uniform part not only increases their strength but also decreases the production sequences and costs. However, achieving this purpose requires sufficient formability of the material. Tube hydroforming is an alternative process to produce complex products. In this process, the higher the material formability the more uniform will be the thickness distribution. In this research, tube hydroforming of aluminum alloy (AA1050) at various temperatures has been investigated numerically to study temperature effect on thickness distribution of final product. Also a warm hydroforming set-up has been designed and manufactured to evaluate numerical results. According to numerical and experimental results in the case of free bulging, unlike the constrained bulging, increase of the process temperature causes more uniform thickness distribution and therefore increases the material formability. 相似文献
11.
Recently, low pressure tube hydroforming has emerged as a technology to reduce the weight of automotive body structures by allowing the implementation of advanced high strength steels and minimizing the number of process steps. In this study, a simplified analytical model based on a rigid, perfectly plastic material model was developed to determine the die closing force needed to form a simple geometry using the low pressure hydroforming process. The analytical solution developed was compared with experimental and numerical results; this demonstrated a reasonable accuracy of the model which will assist in the understanding of the basic principles governing the low pressure hydroforming process. 相似文献
12.
13.
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. 相似文献
14.
15.
16.
Optimized constitutive equation of material property based on inverse modeling for aluminum alloy hydroforming simulation 总被引:2,自引:2,他引:0
Li-hui LANG Tao LI Xian-bin ZHOU B.E. KRISTENSEN J. DANCKERT K.B. NIELSEN 《中国有色金属学会会刊》2006,16(6):1379-1385
1Introduction Sheet hydroforming has many advantages such as high drawing ratio,good part surface,and can be applied widely in the versatile and low volume production with miscellaneous materials such as aluminum alloys,high-strength steel,stainless steel… 相似文献
17.
Hyun Kyu Park Hyae Kyung Yi Chester J. Van Tyne Young Hoon Moon 《Metals and Materials International》2009,15(6):897-902
Safe and robust process design relies on knowledge of the evolution of the mechanical properties in a tube during hydroforming.
The manufacturing of tubular shapes generally consists of three main stages: bending, preforming, and expansion. The latter
is usually called hydroforming. As a result of these three steps, the final product’s strain hardening history is nonlinear.
In the present study, the strain hardening behavior during hydroforming was experimentally investigated. The variation of
local flow stress and/or local hardness was used as an index of the strain hardening during the various steps and the local
flow stress and/or local hardness were used with respective correlations to determine the effective strain. The strain hardening
behavior during hydroforming after preforming has been successfully analyzed by using the relationships between hardness,
flow stress, and effective strain for variable pre-strains prior to hydroforming. The comparison of predicted hardness with
measured hardness confirms that the methodology used in this study is feasible, and that the strain hardening behavior can
be quantitatively estimated with good accuracy. 相似文献
18.
薄壁不锈钢数码相机外壳液压成形工艺研究 总被引:2,自引:1,他引:1
数码相机外壳是形状复杂的非旋转体不规则结构薄壳形件,文章基于其工艺难点及形状特征分析,采用1Cr18Ni9Ti不锈钢板材进行了不同液压加载路径下的充液拉深成形实验,并结合有限元模拟,分析了液压加载与凸模运动的不同匹配关系对成形结果的影响;针对各种成形缺陷分析其产生原因,并确定了合适的成形工艺参数,模拟结果与实验吻合良好。在室温条件下,以1mm/s~2mm/s的凸模速度进行液压成形,在液压载荷最高为20MPa时,成功试制出表面质量好、结构精度高的薄壁不锈钢数码相机外壳。研究结果为复杂结构薄壳形件液压成形工艺参数的确定和优化设计奠定了基础,并为采用液压成形工艺生产和加工电子器件不锈钢外壳提供实验和理论依据。 相似文献
19.
20.
This paper presents recent developments of a simplified finite element method called the inverse approach (IA) for the estimation of large elastoplastic strains and thickness distribution in tube hydroforming. The basic formulation of the IA, proposed by Guo et al. (1990), has been modified and adapted for the modeling of three-dimensional tube hydroforming problems in which the initial geometry is a circular tube expanded by internal pressure and submitted to axial feed at the tube ends. The application of the IA is illustrated through the analyses of numerical applications concerning the hydroforming of axisymmetric bulge, made from aluminum alloy 6061-T6 tubing, the hydroforming of square section hollow component and the hydroforming of a free Tee extrusion from welded low carbon steel LCS-1008 tubing. Verifications of the obtained results have been carried out using experimental results together with the classical explicit dynamic incremental approach using ABAQUS® commercial code to show the effectiveness of our approach. 相似文献