ABSTRACT

Incremental Tube Forming (ITF) is a comparatively new forming process in which the ends of a tube are expanded into the desired shape using a hemispherical tool. ITF process finds its applications in various sectors like automotive, aerospace, and heavy industries for interconnection of the piping system, structural elements, etc. It is crucial to analyze the tube’s deformation behavior for its successful forming and good accuracy of the formed part. The current work investigates the tube’s deformation behavior during the grooving and tube end forming in single and multistage strategies. Both the experimental and simulations are performed to analyze the strain distribution, thickness variation, and formability of the AA6063 tube. The experimental and simulated strain distribution reveals that the bottom end of the tube where forming started is in the plane strain state and the free end of the tube is uni-axial tension. The thickness variation and reduction percentages for experimental and simulations are in agreement with each other. An error of less than 2% was found for thickness variation at all the considered wall angles. Finally, the microstructural analysis performed using electron back scattered diffraction (EBSD) technique has revealed the changes in grain size, local misorientations and grain aspect ratio formed at various wall angles.

摘要

渐进式管成形 (ITF) 是一种相对较新的成形工艺，在该工艺中，使用半球形工具将管的末端膨胀成所需的形状。ITF 工艺在汽车、航空航天和重工业等各个领域得到应用，用于管道系统、结构元件等的互连。分析管的变形行为对于成功成型和成型零件的良好精度至关重要。目前的工作以单级和多级策略研究了开槽和管端成形过程中管的变形行为。进行实验和模拟以分析 AA6063 管的应变分布、厚度变化和可成形性。实验和模拟应变分布表明，管子开始成形的底端处于平面应变状态，管子的自由端处于单轴拉伸状态。实验和模拟的厚度变化和减少百分比彼此一致。在所有考虑的壁角处发现厚度变化的误差小于 2%。最后，使用电子背散射衍射 (EBSD) 技术进行的微观结构分析揭示了在不同壁角形成的晶粒尺寸、局部错误取向和晶粒纵横比的变化。在所有考虑的壁角处发现厚度变化的误差小于 2%。最后，使用电子背散射衍射 (EBSD) 技术进行的微观结构分析揭示了在不同壁角形成的晶粒尺寸、局部错误取向和晶粒纵横比的变化。在所有考虑的壁角处发现厚度变化的误差小于 2%。最后，使用电子背散射衍射 (EBSD) 技术进行的微观结构分析揭示了在不同壁角形成的晶粒尺寸、局部错误取向和晶粒纵横比的变化。