Research Progress on Multi-scale Microstructure Design and Strengthening-Toughening Mechanisms of Discontinuously Reinforced Titanium Matrix Composites

Discontinuously reinforced titanium matrix composites (DRTMCs) exhibit advantages such as light weight, high strength, and heat resistance, demonstrating broad application prospects in aerospace, consumer electronics, and other fields. Inspired by the multi-scale architectures of natural materials, the design of DRTMCs has evolved from uniformly distributed single reinforcements to architecture reinforcement configurations, and further to the coordinated design and regulation of multi-scale reinforcement architectures coupled with hierarchical titanium matrix. This progression has enriched their microstructure, leading to the formation of multi-scale heterogeneous structures. Such structures fully leverage synergistic strengthening mechanisms to enhance strengthening efficiency. Moreover, these composites effectively avoid strain localization to ensure favorable plasticity while maintaining excellent damage resistance. This review summarizes typical configuration design strategies and their evolutionary pathways in DRTMCs, elucidates the underlying strengthening-toughening mechanisms, and proposes future research directions based on current advancements to advance the application of high-performance titanium matrix composites in critical fields.