【作者】 高庆峰；

【导师】 陈伟；

【作者基本信息】 南京航空航天大学 ， 航空宇航推进理论与工程， 2008， 硕士

【摘要】 超塑成形(SPF)是一种高效益、近无余量的先进制造技术,被广泛应用于航空、航天、兵器、汽车等领域。超塑成形过程是一个极其复杂的过程,不仅变形量大,而且成形过程及产品质量受材料性能、摩擦状况、工艺条件、模具结构及加工设备等多种因素的影响。长期以来人们主要是采用基于经验的试错方法进行工艺及模具设计,这使得产品的研发周期较长、费用高,并且产品的质量也不能得到完全的保障。随着计算机及数值计算方法的发展,以有限元法为代表的数值模拟技术已广泛应用于超塑成形过程分析中。利用有限元数值模拟技术可以在计算机上虚拟实现叶片超塑成形的全过程,对预测缺陷的产生、降低生产成本以及保证质量有十分重要的作用。本文讨论了宽弦空心风扇叶片的结构特点和生产方法——超塑成形/扩散连接(SPF/DB)工艺,着重介绍了超塑成形/扩散焊接(SPF/DB)叶片结构及其选材的特点。与其它的生产工艺相比,SPF/DB工艺是先进空心风扇叶片的重要备选方案。根据金属超塑性成形原理,本文对模型空心叶片超塑成形进行了数值模拟的分析。采用ANSYS/LS-DYNA有限元软件对三层和四层板结构空心叶片的超塑成形过程进行模拟。分析结果表明不同的工艺设计参数对空心风扇叶片的超塑成形过程有很大的影响,同时,得到了最佳应变速率下加载的压力-时间曲线,上述研究结果对宽弦空心风扇叶片超塑成形试验的设计提供了理论的参考依据。本文发展了宽弦空心风扇叶片超塑成形的数值模拟方法,为进一步的研究和工程应用提供理论依据和方法。更多还原

【Abstract】 Superplastic forming (SPF) have been widely used in the automobile, aerospace and weapon industries owing to their high efficiency, no margin left advanced manufacturing technology , The SPF is a complex process, Which is affected by material properties, friction condition, technological conditions, structure of dies, and related equipments. So far, the design of technology and dies mainly depends on the engineering experience and involves repeated trial-and-errors. This will result in the long research period and high cost, and the quality of products also can’t be guaranteed absolutely. With the development of computer technologies and numerical methods, the FEM (Finite Element Method) numerical calculation method has been widely used to simulate the SPF process, through which the deformation of the blade can be obtained. All of these can be very helpful to predict occurrence of the defects, to reduce the cost and to guarantee the quality of products.The development of hollow wide chord fan blades is described in this paper. The mechanical characteristic of the fan blades, its manufacturing method SPF/DB(Superplastic Forming/Diffusion Bonding) with particular reference to structural and metallurgical characteristics are discussed. Comparing with the others, the SPF/DB fabrication process is an outstanding candidate for manufacturing advanced hollow blades. According to metal SPF principle,Finite element simulation is presented for the SPF hollow modal fan blades, using ANSYS/LS-DYNA to simulate the multilayer hollow fan blade SPF/DB process. The analysis result showed that the different design parameters have greatly affect on the hollow fan blades SPF process, The curve of the pressure-time is optimized. The results of the study provide a theoretical reference to the design of the SPF hollow fan blades experiments. A kind of the finite element simulation methods of SPF/DB hollow fan blades are developed in this paper as theoretical basis and methods for the further research and engineering applications.更多还原