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用超塑性成形工艺对外侧表面带凸耳的空心圆锥体铝合金(7A04)零件进行了成形试验,通过分析和试验确定了合理的超塑成形工艺和模具结构。该零件须分两步进行超塑成形:先成形空心圆锥体,再成形凸耳;超塑性成形工艺制造该零件比原机加工工艺简单,节省材料超过60%。 相似文献
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针对某光学显微镜粗动手轮零件进行工艺分析,提出用镦挤成形代替原来的切削加工。根据产品零件的要求及成形特点,改进挤压模具结构,通过挤压实验,对模具参数和技术要求进行了修改。得出:1.对于带锥形通孔多台阶的零件,可采用上下凸模来挤压成形;2.对于圆角较小,两断面差较大的成形凸模,可采用组合式而不采用整体式;3.对于有小圆角的凸模,适当降低热处理硬度,提高塑性。生产证明,该模具结构合理,参数合适,利用该 相似文献
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基于SimuFact模拟分析软件,对新能源汽车空心电机轴复合成形工艺的多工序进行数值模拟分析与优化。研究结果表明:在热挤压成形过程中,等效塑性应变主要集中在靠近凸模前端的位置,材料沿轴向两端流动;经过径向锻造后,电机轴空心段的等效塑性应变沿直径方向先减小后增大,台阶段的等效塑性应变沿直径方向逐渐增大。经正交实验优化后的冷径向锻造工艺参数为:锤头相对转角为18°、锤头下压量为1.0 mm、锤头入模角为22°、坯料进给量为1.0 mm。在此基础上,成功地研制出一种通过热挤压结合冷径向锻造复合成形的新能源汽车空心电机轴,并分析了复合成形工艺对空心电机轴的微观组织及晶粒细化的影响。 相似文献
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1引言由于镁合金的比重小、强度高,能承受较大的冲击载荷,并有一定塑性,所以它广泛应用在航空制造业中。但是用镁合金板材来制造空心壳体零件(拉深件)是比较困难的。本文结合某航空仪表零件,并在MB8镁合金板材超塑性研究基础上,对该材料超塑气压成形条件和过程... 相似文献
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结合镁合金带内筋薄壁壳体结构特点,研究出相应的挤压成形新技术,并设计了相关模具装置。模具凸模采用芯轴与轴套过盈配合,只有在受到一定的轴向力的作用下才会发生相对滑动。凸模芯轴受设备上顶杆力的作用下降后,撑住筒形件内孔,凸模外套对较小面积的筒壁进行挤压,筒壁在较小的挤压力作用下被拔高。采用空心坯料、芯轴挤压成形方法提高了材料的利用率和产品成品率,同时明显降低挤压成形力。试验结果表明,该新方法成形力小,制定的工艺和设计的模具合理可行,所成形零件的力学性能、显微组织和尺寸精度均符合要求,为带内筋薄壁壳体零件塑性成形奠定了理论和实践基础。 相似文献
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利用ABAQUS/Explicit有限元分析软件对2A12 O态铝合金橡皮囊成形凸曲线弯边零件起皱现象进行分析,借助正交试验工具,进行了橡皮囊成形数值模拟试验。通过分析材料性能参数和工艺参数对凸弯边橡皮囊成形零件的影响,获取了影响凸曲线弯边零件起皱的主效应参数,并在此试验基础上建立了基于蚁群神经网络的起皱预测模型。在利用大量试验数据对其训练之后,使用该模型预测橡皮囊成形零件的起皱情况,同时对2A12 O态铝合金板材橡皮囊成形凸弯边零件进行工艺试验验证,结果表明:该模型能够在研究新零件成形过程中快速获得最佳成形参数,并且可以提高效率的工业,且预测误差控制在5%以内,且满足工业应用标准。 相似文献
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微型车轮辋滚压成形工艺柳州市汽车运输公司车厢厂(广西柳州545007)杨如第1引言滚压不同于旋压和辊轧,是一种特殊成形方法。其成形原理是:首先将空心零件的毛坯条料卷回并把接口焊合,然后套在专用滚压机主轴凹模轮上,当从动凸模轮以垂直于主轴的运动方向压紧... 相似文献
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Jens Kappes Mathias Liewald Simon Jupp Christoph Pirchl Roman Herstelle 《Production Engineering》2012,6(3):219-228
Relatively low tooling costs, high design complexity coupled with low forming speeds make the superplastic sheet metal forming process attractive, especially for smaller lot sizes. Due to the relatively small lot size, the effort and budget for designing superplastic forming processes is usually limited (Kappes and Liewald in J Mater Sci Eng B1:472?C478, 2011). For this reason the tool design and corresponding pressure profiles in superplastic forming processes are often based on trial and error (Franchitti et al. in 11th international Esaform conference on material forming, 2008; Barnes in J Mater Eng Perform 4:440?C454, 2007). Consequently a process chain should be established to design superplastic forming processes accurately and efficiently. This paper deals with the process chain to form an aluminium part superplastically. At the beginning of the process chain, there is a new, developmental aluminium alloy sheet (AA5456, s0?=?1.6?mm) designed for superplastic forming supplied by Hydro Aluminium Rolled Products GmbH. The relevant material parameters of this sheet are then determined via pneumatic bulge testing with and without in situ measurement of strains. Using these experimentally determined parameters superplastic forming process can be simulated by FE modelling (PAM-STAMP 2G). Due to in situ measurement of strains during pneumatic bulging, the comparison of experiment and FE-simulation results over the whole pneumatic bulging process could be done. This comparison shows good correlation for the observed conditions. Furthermore a cylindrical cup was simulated, evaluated via determined isobar Superplastic Forming Limit Curve (at fracture) and finally formed by pneumatic bulging. Material characterisation of the bottom of this cup showed that excessive cavitation was observed as a result of the iron-silicon particles. Superplastic forming of a bracket usually formed out of AA5083 was also simulated using material parameters of AA5456. The simulation was able to show that this part is not able to be manufactured out of AA5456 under these forming conditions, which was confirmed by forming trials performed at ALU-SPF AG. 相似文献
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对LC4超硬铝合金超塑成形后的固溶时效强化进行了试验研究,发现超塑变形能使固溶及时效过程加快,不易出现晶间无沉淀带,而对最大强化效果影响甚小。 相似文献
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基于板料超塑性变形的特点,本文将超塑性变形全过程分为稳定变形、准稳定变形、应变路径漂移和集中性失稳发展四个阶段,依据增量理论,用数值方法建立了一普遍适用的失稳模型。然后在此基础上,依板料发生集中性失稳(dε_2=0)为许用变形程度的极限,预测了板料超塑变形时的成形极限曲线。对铝合金LY12CZ和半硬态黄铜H62的超塑性实验研究表明:用本文提出的失稳模型预测的超塑性板料的成形极限与实验结果具有较好的一致性。 相似文献
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George Luckey Jr. Peter Friedman Klaus Weinmann 《Journal of Materials Processing Technology》2009,209(4):2152-2160
The conventional superplastic forming (SPF) of complex and deep geometries can result in excessive thinning and necking. To address these issues, a two-stage SPF process has been developed and demonstrated in forming trials using a superplastic aluminum sheet alloy. Within a single die, gas pressure is used to form the blank into a preform die cavity prior to the pressure being reversed to form the sheet into the final component cavity. The preforming of the blank creates length of line, while preserving metal thickness in certain regions to improve the thickness profile of the final part. In this work, a preform has been designed to improve the forming of a complex component by providing a superior thickness profile as compared to a conventional single stage forming cycle. Finite element analysis was used to guide the design of the preform cavity since the preforming surface was not intuitive and could cause wrinkling in the final part. 相似文献
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The present paper deals with superplastic forming of aluminium alloy AA5083 sheet metals tested at specific strain rates, temperatures and counter pressures by means of bulge testing using circular and elliptical dies and by the cone-cup testing method. Further, differences from batch to batch can lead to a different strain rates at the maximum m value. It is shown by experimental investigations that pulsating strain rates can lead to higher m values and to increased thickness strains. 相似文献
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大块非晶合金超塑性变形的研究现状与发展 总被引:1,自引:0,他引:1
文章对国内外非晶合金超塑性基本性能的研究工作进行了介绍和评述。根据材料成形工艺的要求,提出了非晶合金超塑性成形研究的内容。介绍了非晶合金超塑性拉伸实验和压缩实验的研究进展,分析了温度和成形速率对变形的影响,介绍了粘度的影响因素,对这些研究内容和热点问题进行了评述。展望了非晶合金超塑性研究的发展趋势,提出应加强非晶合金超塑性流动过程的理论研究。 相似文献
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综述了高应变速率超塑材料种类、变形机理和应用技术的最新进展。高应变速率超塑材料主要是铝基复合材料及铝合金,最近,对镁合金、纳米材料、钛合金高应变速率超塑性能的研究也已开始。高应变速率超塑性在工业中的应用已经起步,例如快速超塑成形技术、一模多件技术等,可以实现中等批量、甚至大批量生产,但是主要集中在铝合金上。未来激光辅助超塑成形技术、电塑性辅助超塑成形技术值得期待。 相似文献