共查询到20条相似文献,搜索用时 156 毫秒
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以丰田IMV皮卡转向节的热锻工艺为研究对象,采用Deform-3D软件对38MnSiVS5非调质钢转向节的热锻成形过程进行有限元模拟,分析了该转向节辊锻毛坯头部直径的尺寸设计对成形载荷、坯料成形充模效果的影响,研究了阻力墙在热锻成形过程中对锻坯中金属流动和充填的作用。模拟结果表明:适当增加辊锻坯料的头部直径有助于金属充模,但直径过大会导致成形载荷急剧上升;为了促进转向节头部5个叉的成形,并避免辊锻坯料直径过大,有必要通过设置阻力墙迫使金属向合理方向流动。热锻成形试验表明,优化工艺后的转向节成形锻件的充填效果得到明显改善。 相似文献
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汽轮机叶片是将蒸汽能转换成机械功的关键部件,叶片精锻是叶片锻造的发展趋势.本文利用数值模拟方法,仿真了叶片金属在锻模型腔内的流动和成形过程,论述了摩擦条件对叶片精锻成形规律的影响.在锻坯金属变形充模的3个阶段,分析并讨论了不同的界面摩擦因子m对叶片模锻成形规律和模具失效的影响.数值实验结果表明:随着界面摩擦因子的增加,克服坯料金属界面流动阻力所需的附加模锻载荷增加,叶片锻件不同区域内的最大最小温度差、最大最小等效应变差,以及最大最小等效应力差增加;与此同时,锻模型腔局部最大等效应力和最大温度也增加. 相似文献
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为选择合适的等温精密成形工艺,获得综合性能优良的铝合金旋转盘锻件,采用有限元法模拟分析了两种不同坯料条件下旋转盘锻件等温精密成形时的金属流动规律,并通过镦粗、预锻制坯和终锻工艺成形出了外形完美、综合性能优良的铝合金旋转盘锻件。结果表明:采用环形坯料成形时金属主要沿径向充填模膛,易产生充不满缺陷,而采用五角形坯料则使金属材料主要沿轴向充填模膛,可以预防该类缺陷的发生。虽然环形坯料在分模面的投影面积较五角形坯料的小,成形时所需载荷却大得多。因此,五角形坯料是等温精密成形旋转盘锻件的最佳坯料方案。 相似文献
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针对高压容器用端盖类铸件合格率低的问题,本文提出了等温锻造成形方式。同时,依据端盖的结构特点设计了合理的预锻坯料结构和尺寸,使等温锻造过程中金属的变形更均匀。以端盖难充填部位的充填率为优化目标,优化了预锻坯料结构,改善了成形件的质量。结果表明,采用锻造生产20Cr Mn Ti钢端盖零件是可行的。 相似文献
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Feng Li Jun Feng Lin Guan Nan Chu 《JOM Journal of the Minerals, Metals and Materials Society》2009,61(8):57-60
To research impeller parts flow behaviors in the die forging process, the finite element method is used to study the deformation
flow behavior of different shapes in the blank forming process. The results show that the blade parts of the forgings were
hard to fill, but with the section of the blade shifting down, the metal has a marked trend to flow toward this area of the
die cavity. Compared with a cylindrical shape, the die cavity of the blade part can be filled more easily and the uniformity
of metal flow will increase. Using a ladder shape to manufacture forgings of impellers can meet requirements for design and
properties. 相似文献
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In this work, a novel forging technology has been developed to produce a magnesium alloy impeller with twisted blades of micro-thickness used in a fuel cell system. Due to the very complicated blades of the impeller, a specially designed split die was adopted for successful forging of the impeller. In this split die-set, the coherence of reinforcement ring and split dies is induced by forging pressure which increases with increasing forging load. Both the reinforcement ring and the split dies have appropriate tapers so that during the forging process they are consolidated to allow no gap between the split dies and are separated easily after forging. This novel technology can provide the near net-shaped impeller without the burr generation when split dies are used. Based on the newly developed technology, the impeller forging experiments were carried out using magnesium alloy AZ31 which had been microstructurally refined through equal channel angular pressing (ECAP). The tensile and thermal stability tests were carried out under various levels of temperature and strain rate to find optimum processing conditions for precision impeller forging. Finally, the changes in microstructure and microhardness at the various positions of the forged impeller were investigated to compare with those of the initial billet. It has thus been shown that the proposed new method is effective to achieve precision forging of a magnesium alloy with high precision. 相似文献
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参照实际大型筒体件的锻造扩孔工艺,建立一组缩小比例尺寸的筒体几何模型及相关加工过程数据,通过DEFORM仿真模拟,研究了大型筒体件扩孔工艺的变形规律,输出了扩孔变形过程的2D/3D数据分析结果,研究了筒体件的形状因子、砧型、锻造温度及压下率对扩孔变形的影响,从而确定最佳扩孔工艺参数,研究结果对实际RPV等大型筒体件锻造生产有重要参考价值。 相似文献
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根据叶轮的形状特点,改变传统的加工方法,通过对叶轮加工过程的分析,选择合理的编程策略、走刀路径及进退刀方式。根据材料的切削力、切削热和切削表面粗糙度值,选择合理的切削参数,应用PowerMill软件进行仿真加工后,采用五轴加工中心加工出零件,提升叶轮的综合机械性能。 相似文献
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锻造成形微观组织优化建模及应用 总被引:8,自引:0,他引:8
以锻件晶粒度分布的均匀性与细小化为目标,建立了锻造变形过程的微观组织演变模型,并给出了优化目标函数表达式。采用刚塑性有限元和遗传优化算法相结合,开发了微观组织模拟与优化软件,并对典型的圆柱体镦粗工艺过程进行了微观组织模拟与优化。优化结果表明,影响变形均匀性的摩擦因素显著影响成形后的微观组织晶粒度的分布均匀性和细小化,同时对其它工艺因素的优化也能一定程度地实现对最终锻件组织均匀和细小化的控制。研究结果表明,在有限元数值模拟基础上建立微观遗传优化算法,能够对锻造等金属体积成形过程中的工艺参数与材料状态参数等实施优化,以达到通过控制成形工艺因素来优化微观组织,而实现提高产品性能的目的。 相似文献
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大型异形铝铸件的铸造工艺研究 总被引:1,自引:1,他引:1
大型异形铝铸件,铸造工艺难度较大,常需依赖于丰富的生产经验辅之以计算机凝固模拟分析技术。针对不同的形状,制定相应的铸造工艺。对管体、轮毂、支腿垫块、螺旋桨等典型产品较为成熟的生产工艺进行介绍。通过对这些典型铸件的工艺案例进行分析,探讨大型异型铝铸件的铸造工艺设计方法。 相似文献
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Isothermal precision forging is applied to manufacturing 7075 aluminum alloy disk workpiece with complex shape. By combining experiment with FEM (finite element method), the mechanism as well as the evolution with respect to the defects of the flow lines is studied in the isothermal precision forging of the workpiece. The results show that the flow lines of disk forging with complex shape are influenced mainly by the flow lines of the die forging billet. The radial flow lines distribute along the forging shape more easily than that the axial flow lines do. The fibre breaking is mainly caused by too much redundant metal flowing fast along the radial direction in the late stage of die pressing. In the end, some reasonable measures are put forward to optimize the flow lines. 相似文献