共查询到19条相似文献,搜索用时 171 毫秒
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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
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面向枝杈类锻件挤压成形过程中的折叠缺陷,基于正交设计法,采用数值模拟与实验相结合的方法研究成形参数对折叠缺陷的影响。数值模拟结果表明:折叠长度随冲头底锥相对直径d/D(d为冲头底锥直径,D为挤压筒直径)、枝杈角度α的增大而增大,随枝杈根部圆角半径r、模具圆弧外端与冲头环形平面距离h的增大而减小。通过极差分析,发现对折叠长度的影响程度依次为:冲头底锥相对直径d/D,模具圆弧外端与冲头环形平面距离h,枝杈角度α,圆角半径r。挤压成形实验的实验结果与数值模拟结果相吻合,验证了数值模拟的准确性,可供枝杈类锻件的无缺陷锻造参考。 相似文献
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为降低直齿圆柱齿轮冷挤压成形载荷和改善齿形角隅部分充填性,在分析直齿圆柱齿轮成形过程中金属流动特性基础上,提出了采用可控运动凹模的成形工艺。利用Deform-3D软件对此成形工艺过程中的金属流动规律、成形载荷、成形缺陷进行了数值模拟分析,并对该工艺进行了优化。分析结果表明,当凹模速度为冲头速度的1/2时,成形过程中齿形充填均匀、齿形角隅部分充填饱满,成形载荷最小,较传统单向挤压成形载荷降低了约20%。对优化后的成形工艺进行了成形试验研究,试验成形齿轮齿形饱满,无塌角缺陷,试验结果与模拟结果基本吻合。 相似文献
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用DEFORM-3D模拟软件,对镁合金汽车控制臂等温热模锻成形工艺过程进行了数值模拟。得到了锻造变形过程中的等效速度场、等效应力场的分布。结果表明,在模锻温度400℃,上模工作速度3 mm/s时,成形的AZ81镁合金控制臂质量较好。 相似文献
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为优化模具结构,减少缺陷的产生,研究了轴承套圈反挤压过程中的应力、应变和载荷.以某轴承型号为例,使用Deform软件对轴承套圈反挤压过程进行数值模拟,比较了不同的冲头倒角和料芯厚度与冲头载荷之间的关系.结果显示,冲头倒角在4mm时载荷最小,料芯厚度小于7.5mm时冲头载荷显著增大.实际生产结果表明,使用模拟参数设计的模... 相似文献
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AZ31镁合金板的热拉深性能 总被引:26,自引:3,他引:26
通过热轧工艺制备了厚度为0.8 mm的AZ31镁合金薄板. 在不同温度和应变速率条件下进行了单向拉伸试验. 在50~240 ℃的温度范围内, 采用平底杯形冲头拉深试验研究了成形温度、拉深速度以及冲头温度对AZ31镁合金板热拉深工艺的影响. 结果表明 AZ31镁合金热轧薄板的RLD随温度的升高而明显增大; 在成形温度为200 ℃, 拉深速度为30 mm/min的条件下, 最大RLD可达2.65, 相应的高径比为1.4, 证明AZ31镁合金板具有良好的热拉深性能; 此外, 拉深速度和冲头温度对AZ31镁合金的拉深成形也有重要影响. 相似文献
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AZ31镁合金板材温热冲压数值模拟与实验研究 总被引:9,自引:0,他引:9
采用Gleeble3500热模拟实验机进行了单向拉伸实验,分析了AZ31镁合金板材的力学性能;以此实验数据为基础,对温热冲压过程进行了数值模拟,研究了拉深温度、压边力等工艺因素对镁合金板材成形性能的影响;通过极限拉深比实验,对数值模拟结果进行了实验验证。结果表明:在极限拉深温度150℃,极限拉深速度15 mm/s,固定压边力的工艺条件下,极限拉深比能够达到2.5。模拟结果表明:模拟结果和实验结果具有良好的一致性;采用变压边力可以明显提高板材的冲压性能,极限拉深比将达到5.0。 相似文献
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基于Dynaform软件平台,建立了Y型异径三通管三维弹塑性有限元模型。运用数值模拟方法,研究了AZ31镁合金Y型异径三通管热态内高压成形过程、成形缺陷、等效应变分布。探讨了初始管坯长度、左右冲头轴向进给量与成形支管高度之间的关系;研究得到了相同支管长度下成形不同Y型夹角三通管所需的左右冲头进给量。结果表明:随着初始管坯长度减小,支管高度随之增加;在左右进给量相同的情况下,左侧金属流向支管阻力更小,支管高度增加明显;随着Y型夹角的增大,右侧冲头进给增加,轴向补料比减小,总补料比增加,当夹角为90°时,左右补料相同。 相似文献
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K. Mori S. Nishijima C.J. Tan 《International Journal of Machine Tools and Manufacture》2009,49(10):767-772
A two-stage cold stamping process for forming magnesium alloy cups having a small corner radius from commercial magnesium alloy sheets was developed. In the 1st stage, a cup having large corner radius was formed by deep drawing using a punch having large corner radius, and the corner radius of the cup was decreased by compressing the side wall in the 2nd stage. In the deep drawing of the 1st stage, fracture was prevented by decreasing the concentration of deformation with the punch having large corner radius. The magnesium alloy sheets were annealed at 500 °C to increase the cold formability. Circular and square cups having small corner radii were formed by the two-stage cold stamping. For the circular cup, the height of the cup was increased by ironing the side wall in the 1st stage. The radii of the bottom and side corners of the square cup were reduced by a rubber punch for applying pressure at these corners in the 2nd stage. It was found that comparatively shallow magnesium alloy square cups used as cases of laptop computers and mobile phones can be satisfactorily formed at room temperature without heating by the two-stage stamping. 相似文献
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Lihui Lang Huili Li Shijian Yuan J. Danckert K.B. Nielsen 《Journal of Materials Processing Technology》2009,209(5):2553-2563
Tube hydroforming is a process for manufacturing of lightweight components, especially automotive parts, with advantages of cost and weight reduction, better structural integrity and increased strength and stiffness over the conventional stamping process. Generally, the hydroformed parts can be obtained by multi-stages made up of bending, pre-forming and finishing. Based on the characters of FEM and using the useful wrinkles, the process of multi-stages was investigated by using an aluminum alloy. For avoiding the typical failure modes such as folding back, wrinkling, buckling and fracture due to unreasonable selection of the internal pressure and the axial punch feeding, the optimization strategy was created and the process parameters were optimized by using “useful” wrinkles instead of “harmful” wrinkles in the pre-forming stage and in the finishing stage. The suitable pre-forming die cavity shape was discussed. The results from simulation keep a reasonable agreement with that from experiment. 相似文献
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Numerical optimization technique coupled with finite element analysis of the stamping/sheet hydroforming process was developed to predict four possible modes for application of blank holder force (BHF) in multiple-point cushion systems, namely a) BHF constant in space/location and time/stroke, b) BHF variable in time/stroke and constant in space/location, c) BHF variable in space/location and constant in time/stroke and d) BHF variable in space/location and time/stroke. The BHF was predicted by (a) minimizing the risk of failure by tearing (thinning) in the formed part and (b) avoiding wrinkling. The developed technique was applied to predict the BHF to form a) an automotive part (liftgate-inner) from AA6111-T4 aluminum alloy, b) an asymmetric part from aluminum alloy AA5083-H32 by sheet hydroforming process with die (SHF-D) and c) a round cup by sheet hydroforming with punch (SHF-P). Experimental results showed that the FEM based optimization methodology can reduce trial and error effort and is able to predict the blank holder force necessary to form the parts without fracture and wrinkling in the investigated stamping and sheet hydroforming operations. 相似文献
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三通管内高压成形时壁厚影响因素的研究 总被引:1,自引:0,他引:1
分析了传统内高压成形三通管的成形过程,通过理论分析并结合试验和模拟进行比较,对比得出了加载路径、填充介质以及模具的圆角半径对内高压成形件的壁厚分布的影响,对工业生产有实际指导作用. 相似文献