共查询到20条相似文献,搜索用时 406 毫秒
1.
2.
3.
目的 采用热塑性挤压法进行近净成形,以克服铝合金切削法工序多、加工余量大、材料利用率低的缺点。方法 利用Deform-3D软件对翼座热塑性成形过程进行数值模拟,分析比较了单向挤压、双向挤压过程的特点、成形效果及所需加载载荷大小。结果 在模拟过程中,单向挤压方案与双向挤压方案均出现了挤压缺陷,通过增加压余厚度成功解决了双向挤压方案的挤压缺陷,且双向挤压所需最大载荷要小于单向挤压。结论 双向挤压方案要优于单向挤压方案。对双向挤压方案进行试验试制,获得了健全的铝合金翼座,为零件大批量生产提供了有力支持。 相似文献
4.
5.
目的分析挤压成形中车用下轴套零件成形表面出现的折叠缺陷,优化挤压上凹模的底部出口斜度、下凹模的入口斜度和挤压深度等主要成形工艺参数。方法采用DEFORM-3D软件,对汽车下轴套零件的冷挤压成形工艺进行了系统的有限元数值模拟试验。结果挤压成形模具结构设计不合理,导致在成形过程中模具分型面处金属出现汇流并形成折叠。结论通过优化挤压模具结构,使金属成形良好,无折叠缺陷出现,最终获得了较为合理的冷挤压模具结构。 相似文献
6.
目的 探究新能源汽车空调压缩机涡旋盘静盘成形技术及成形过程,解决新型涡旋盘外圈充填不满的缺陷问题。方法 采用背压挤压与闭式挤压结合的工艺方案,利用有限元技术对成形过程进行数值模拟分析,然后结合物理实验对工艺可行性进行验证。结果 获得了成形过程中金属流动规律、载荷变化曲线、应力应变分布和实际成形样件,并将终锻过程分为3个阶段:第1阶段主要是成形涡旋基底;行程到达30%时进入第2阶段,第2阶段成形外圈和涡旋部分,外圈金属流动较涡旋部分金属流动更快,外圈成形完整;行程到达84%时进入第3阶段,成形涡旋的中间部分。终锻过程中,涡旋根部由于形变量较大,存在应力集中现象。终锻快结束时,外圈已经充满,顶部应力增大。结论 成形中预锻的外圈保证了金属的充填,成形完整,成形工艺可行,“两步法”成形可以获得质量良好的涡旋盘。 相似文献
7.
8.
目的 解决大截面铝合金带筋方筒构件在反挤压过程中成形力大的难题,实现在3 000 t压力机下成功制备内孔为665 mm×665 mm的大截面带筋方筒形构件。方法 提出了一种使用新型棱台凸模结构代替平凸模结构的方法,用主应力法得出了棱台凸模结构与平凸模结构的挤压力计算公式,对比分析了2种凸模结构反挤压成形力的大小,并用DEFORM有限元软件模拟分析了不同结构参数下的棱台凸模反挤压过程,最终进行工程试制,验证了反挤压工艺的可行性。结果 通过主应力法得出了方筒形件的变形力计算公式,得出棱台凸模结构反挤压成形力小于平凸模结构反挤压成形力,经模拟分析得出在反挤压过程中棱台凸模结构的最优结构参数为棱台斜角15°、棱台高度40 mm,并在3 000 t压力机上成功制得内孔为665 mm×665 mm的大截面带筋方筒形构件。结论 通过数值模拟分析可知,与采用平凸模结构相比,采用棱台凸模结构时的反挤压成形力降低了约13%,同时减少了挤压变形过程中的金属流动“死区”。经实验验证,在3 000 t压力机上成形了内孔为665 mm×665 mm的大截面带筋方筒形构件,实现了省力挤压。 相似文献
9.
目的针对TU1触头托零件工艺中加工效率低、生产成本高、加工后得到的零件表面质量难以达到要求等缺点,提出了一种新的冷精锻成形工艺方案。方法利用Deform-3D软件对其成形过程进行数值模拟分析,得到变形挤压力及等效应力应变分布规律。结果利用一次挤压能够完全成形斜边槽及端面台阶,并且在此基础上设计了触头托成形模具,通过实验方法成形出了尺寸精度和表面质量均符合要求的零件。结论表明了该工艺方案和模具结构设计的可行性和实用性,为触头托零件的批量生产提供了一种更经济有效的方法。 相似文献
10.
目的研究空心阶梯轴温挤压成形的可行性。方法根据空心阶梯轴的结构特点,确定了成形方案,并利用Deform-3D软件进行了有限元数值模拟分析,对成形方案进行了验证。结果根据模拟结果得出,锻件的成形效果较好,没有出现充不满和折叠等缺陷,尺寸精度也较好。结论采用温挤压成形工艺成形空心阶梯轴,获得了满足尺寸要求的空心阶梯轴,成形过程稳定可靠,成形工艺可行。 相似文献
11.
Analytical and numerical modeling of metal forming processes has been studied by many researchers during the past decades. So far, several methods have been introduced to model material behavior during forming processes. In this research, the analogy between the classical plasticity theorem and electrostatic field line formation has been investigated for the first time. It is shown that the velocity potential function of movement in the plasticity and the charge-free electrostatic field are both in the form of Laplace’s relation. The aim of the current research is to model the metal forming processes using the equations governing the electrostatic fields. To demonstrate the effectiveness of the proposed method, the extrusion process is used as the benchmark. A three-dimensional CAD model of the deformation region is constructed and two different voltages are applied to the entry and exit sections based on the geometrical and extrusion parameters. Then, the Laplace’s relation is solved numerically and the relative extrusion pressure, particle flow path in the deforming region, and maximum plastic strain are calculated.To verify the proposed method, different sections are modeled and the results are compared with those in the literature. Finally, some experimental tests are conducted for the extrusion process of the round billets to complex sections. Significant agreement has been observed between the experimental results and the analytical ones. It is shown that the extrusion process could be modeled easily and accurately using the mathematical formalism of the electrostatics. 相似文献
12.
13.
14.
15.
16.
17.
18.
Simulation of liquid infiltration and semi-solid extrusion for composite tubes by quasi-coupling thermal-mechanical finite element method 总被引:7,自引:0,他引:7
Le-Hua Qi Zhong-Ke Shi He-Jun Li Pei-Ling Cui Hong-Mei Han 《Journal of Materials Science》2003,38(17):3669-3675
As a new metal forming technology, the liquid infiltration and semi-solid extrusion process can produce various composite parts, such as tubes, bars, and shaped products, in a single process. In this paper, the liquid infiltration and semi-solid extrusion process for forming a composite tube is simulated by means of thermal rigid-plastic quasi-coupling FEM method. The key technologies such as the handling of liquid phase zone, the transition between liquid and solid phase zones, the grid re-meshing method and the establishment of the boundary condition have also been studied. Based on the FEM simulation software developed by the authors and the grid re-meshing technology, the distribution of stress field, strain field and deformation force in the liquid infiltration and semi-solid extrusion process for forming composite tubes are obtained. The deformation force simulation results accord with the experimental data, indicating the reliability of the system. Therefore, the present research is theoretically valuable in the product quality control and the process parameter choice. 相似文献
19.
In microforming, handling and transporting of meso/micro-sized intermediate preforms are difficult due to the influence of adhesive force on preform surfaces. In this research, the fabrication of meso-scaled bulk cylindrical and flanged parts by directly using sheet metal is investigated. The cylinder is made with a single stroke by shearing, while the flanged part is formed progressively via multi-stage shearing and extrusion. In forming of the flanged part, an intermediate preform is fabricated with sheet metal and a pre-pierced hole for positioning. The final part is blanked out from the sheet metal in the last operation. In such a way, the transporting, positioning and ejecting of the flanged part are facilitated. Furthermore, the characteristics of the developed meso-scaled forming process are extensively investigated. The shearing and fractured surfaces on both the cylindrical and flanged parts are found. The surface grains of the blanked cylinder have undergone severe deformation and been hardened, which increases the flow stress of the blanked cylinder. In addition, the longer cylinder and flanged part are obtained with fine-grained material. This implies that a larger amount of material flow to the lateral side of the workpiece in the case of coarse-grained material. 相似文献