Abstract Knowledge of the deformation mechanics in single point incremental forming of tubes is of great importance to understand the physics behind failure and the workability limits in thin-walled tube expansion. Which are the states of stress and strain in the small localized plastic deformation region between the tube and the single point forming tool, and how damage accumulates until fracture are important questions that this paper seeks to address by means of an analytical model based on membrane analysis. Comparisons are made against conventional tube expansion with a rigid punch to explore the main differences between the two processes regarding the states of stress and strain, the accumulation of damage and the likely mode of failure. The investigation is supported by experimentation performed in aluminium AA6063-T6 and shows that differences in deformation mechanics allow incremental tube expansion to withstand slightly higher values of damage before cracking than conventional tube expansion.

中文翻译：

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管材单点增量成形理论

摘要 管材单点渐进成形的变形力学知识对于理解薄壁管膨胀的失效背后的物理原理和可加工性限制非常重要。管子与单点成形工具之间的小局部塑性变形区域的应力和应变状态以及损伤如何累积直至断裂是本文试图通过基于膜分析的分析模型解决的重要问题. 与使用刚性冲头的传统扩管进行比较，以探讨两种工艺在应力和应变状态、损伤累积和可能的失效模式方面的主要差异。