薄壁纯钛管数控弯曲成形性能研究

Formability of thin-walled commercial pure titanium tube upon rotary draw bending

摘要:

本文研究了薄壁纯钛（CP-Ti）管在不同弯曲半径和不同材料性能下的多缺陷约束数控弯曲成形性能，通过显式/隐式三维有限元模型和实验研究了先进轻量化材料CP-Ti的成形潜力。主要结论如下：1）管材的硬化指数、厚向异性指数和杨氏模量的变化对弯曲成形性能有很大影响；2）与壁厚减薄和截面畸变相比，起皱失稳是抑制大直径薄壁CP-Ti管弯曲成形性能的主要缺陷。升高温度可以提高CP-Ti管的弯曲成形性能，特别是抗起皱性能。

Abstract:

Under variations of bending radii and material properties, the multi-defect constrained formability of thin-walled commercial pure titanium (CP-Ti) tube is identified to explore the forming potential of this advanced lightweight material via explicit/implicit 3D-FE models and the experiments. The major results show that: 1) The variations of hardening exponents, thickness anisotropy exponent and Young’s modulus, have great effects on bending formability; 2) Compared with the wall thinning and cross-section deformation, the wrinkling instability is the dominant defect to restrain the bending formability of the large diameter thin-walled (LDTW) CP-Ti tube. The bending formability of CP-Ti tube, especially the anti-wrinkling capability, can be improved at elevated temperatures.