Strategies and limits in multi-stage single-point incremental forming
Strategies and limits in multi-stage single-point incremental forming
复制标题
多阶段单点渐进成形的策略和限制
DOI：
10.1243/03093247jsa574
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
Niels Bay
中科院分区：
文献类型：
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作者：
M. Skjoedt;M. B. Silva;Paulo A.F. Martins;Niels Bay
多阶段单点渐进成形 (SPIF) 是一种最先进的制造工艺，可以小批量生产具有垂直壁的复杂钣金零件。本文重点介绍多级 SPIF 的应用，旨在生产具有垂直壁的圆柱形杯子。该策略包括在第一阶段形成具有锥角的圆锥形杯，然后是三个后续阶段，逐渐将圆锥形状移向所需的圆柱形几何形状。研究包括材料表征、成形极限曲线和断裂成形极限曲线 (FFLC) 的确定、数值模拟和实验，即实际多级零件中应变路径和断裂应变的评估。数值模拟与实验的评估表明计算和测量的应变和应变路径之间具有良好的一致性。结果还表明，多级成形顺序对主应变空间中应变点的位置有很大影响。应变路径在第一阶段是线性的，而在后续成形阶段是高度非线性的。总体结果表明，实验确定的 FFLC 可以成功地用于确定多级 SPIF 的成形极限。
Multi-stage single-point incremental forming (SPIF) is a state-of-the-art manufacturing process that allows small-quantity production of complex sheet metal parts with vertical walls. This paper is focused on the application of multi-stage SPIF with the objective of producing cylindrical cups with vertical walls. The strategy consists of forming a conical cup with a taper angle in the first stage, followed by three subsequent stages that progressively move the conical shape towards the desired cylindrical geometry. The investigation includes material characterization, determination of forming-limit curves and fracture forming-limit curves (FFLCs), numerical simulation, and experimentation, namely the evaluation of strain paths and fracture strains in actual multi-stage parts. Assessment of numerical simulation with experimentation shows good agreement between computed and measured strain and strain paths. The results also reveal that the sequence of multi-stage forming has a large effect on the location of strain points in the principal strain space. Strain paths are linear in the first stage and highly non-linear in the subsequent forming stages. The overall results show that the experimentally determined FFLCs can successfully be employed to establish the forming limits of multi-stage SPIF.