SBIR Phase I: A Double Sided Incremental Forming System for Rapid Dieless Sheet Metal Fabrication

这个小型企业创新研究(SBIR)第一阶段项目将解决与创新的无模具板材成形工艺-双面渐进成形(DSIF)商业化相关的关键技术挑战。在板材的两侧使用一个小的半球形端部刀具，每个刀具沿着预定的刀具路径移动，从而使外围夹紧的金属板材零件局部变形。现有的刀具轨迹生成方法没有考虑板材在成形过程中的变形机理，导致成形时间过长，几何精度不令人满意。这项研究将创建新的自动化刀轨设计方法，在保持用户定义的吞吐量的同时，考虑板材在DSIF过程中的变形机理，以实现500？m或更低的零件精度。此外，还将设计一个新的DSIF成形中心，该中心可以使用高强度合金来成形大型零件，这些零件需要较高的机械刚度和成型力。这项工作将为将板材零件的快速成型和小批量生产商业化提供重要的科学和技术基础。该项目的更广泛的商业潜力是通过消除对昂贵模具的需求，显著降低高质量板材零件的快速成型和小批量制造的成本。将变形力学引入到刀轨规划中，将在刀轨和成形产品的最终几何形状和应力之间建立强有力的联系。因此，优化刀具路径生成的迭代实验程序将被结构化、科学和更健壮的刀具路径生成方法所取代。与传统成形相比，直接成形成形的优势包括不需要昂贵的形状专用工具(每个高达100万美元)、更高的成形性(高4倍)和更小的成形力(降低30%)。更大的可成形性将允许轻量化和提高燃油效率，从而进一步节省能源。由于只需要电子格式的零件模型来重新制造零件，存储传统模具组的成本将被DSIF消除。

This Small Business Innovation Research (SBIR) Phase I project will resolve key technical challenges associated with the commercialization of an innovative die-less sheet metal forming process, Double Sided Incremental Forming (DSIF). DSIF locally deforms a peripherally clamped sheet metal component using a small hemispherical ended tool on either side of the sheet, each moving along a pre-determined tool path. Current toolpath generation methodologies do not take into account the mechanics of sheet deformation during the forming process, resulting in unacceptably high forming time and unsatisfactory geometry accuracy. This research will create new automated toolpath design methodologies which account for the deformation mechanics of the sheet metal during DSIF to achieve part accuracies of 500 ìm or less while maintaining a user defined throughput. Additionally, a new DSIF forming center will be designed that can form large components using high strength alloys, where high machine stiffness and forming force are required. This work will provide a significant scientific and technological foundation towards commercializing DSIF for rapid prototyping and low volume production of sheet metal parts.The broader/ commercial potential of this project is to significantly reduce the cost of rapid prototyping and low volume fabrication of quality sheet metal components by eliminating the need for expensive die sets. The inclusion of deformation mechanics into DSIF toolpath planning will establish a strong connection between the toolpath and the final geometry and stresses of the formed product in DSIF. Consequently, the iterative experimental procedure for optimum toolpath generation will be replaced by a structured, scientific and more robust toolpath generation methodology. The advantages of DSIF as compared to conventional forming include absence of expensive shape specific tooling (up to $1M each), higher formability (4 times higher) and reduced forming forces (30% lower). Greater formability in DSIF will allow light-weighting and enhanced fuel efficiency, leading to further energy savings. The cost of storing legacy die sets will be eliminated by DSIF, since only part models in the electronic format will be needed for re-fabrication of parts.