钛合金大型复杂构件等温局部加载近β锻造组织控制研究进展

Advances in Microstructure Control during Isothermal Forming of Ti-Alloy Large Complex Components by Near-β Local Forging

高性能钛合金大型复杂构件精确塑性成形是航空航天高端装备实现大运力、低能耗、长寿命的必然选择,然而,面临如何提高成形制造能力和如何实现成形成性一体化控制的挑战。等温局部加载近β锻造为该类构件的成形提供了一种先进的工艺途径。由于成形过程的特殊性、构件结构的复杂性以及钛合金组织对成形方式与条件的敏感性,使得如何实现微观组织控制并获得性能优异的三态组织成为该成形技术研究发展与应用迫切需要解决的关键问题和基础性难题。从钛合金等温局部加载多道次成形组织演化机制、不同加载区和过渡区组织均匀性控制和三态组织形成及等温局部加载参数优化进行分析并给出了最新的研究进展。

High-performance large complex components of Ti-alloy have become the inevitable choice for aerospace high-end equipment to achieve large carrying capacity,low energy consumption,long life.The precision plastic forming of these large complex Ti-alloy components faces two large challenges,such as how to improve manufacturing capacity and how to implement an integrated regulation of forming and performance.Isothermal near-β forging by local loading provides an advanced technology for the forming of such components.However,due to the particularity of forming process,complexity of component in structure and sensitivity of Ti-alloy microstructure to forming way and conditions,the microstructure control and how to get tri-modal structure with excellent performance become a key problem to be solved urgently for research,development and application of this forming technology.This paper presents analysis and state of the art from aspects such as microstructure evolutionary mechanisms of Ti-alloy during multi-pass isothermal local loading forming,microstructural uniformity control of different loading regions and transition regions,formation of tri-modal structure and parameters optimization of isothermal local loading.