Synergistic effects of interstitial elements and TiB to overcome strength-ductility trade-off in titanium matrix composites
Abstract
High-strength titanium matrix composites commonly show an inherent strength-ductility trade-off dilemma, which restricts their wide-range applications. Herein, we achieved synergistic strengthening of Ti-6Al-4V matrix composites by interstitial C, N, and TiB via powder metallurgy and obtained ultra-high tensile strength (1510±5 MPa) and good elongation (8.7 %±0.3 %). In situ-formed TiB promotes equiaxialization of matrix grains, hinders grain growth, and provides numerous nucleation sites for dynamically recrystallized grains. By evaluating the distribution of interstitial C and N in the Ti-6Al-4V matrix and their effects on the stability of the TiB/Ti interface, first-principles calculation results demonstrated that C and N tend to occupy the octahedral interstitial positions in α-Ti, thus inducing lattice distortion and significantly enhancing the (001)TiB/(0001)α-Ti interfacial strength. In addition, quasi-in-situ electron backscatter diffraction under tensile tests revealed the influences of interstitial C and N on the deformation mechanism of the composites. Interstitial C and N promote the activation of 〈c + a〉 dislocations in composites and increase the proportion of pyramidal 〈c + a〉 slip systems. The simultaneous activation of multiple slip systems is the primary factor in improving the composites’ ductility. Experimental and theoretical calculation results in this work provide a new strategy for designing and fabricating ultra-high-strength titanium matrix composites without sacrificing their ductility.
Document Type
Journal Article
Date of Publication
7-1-2026
Volume
258
Publication Title
Journal of Materials Science and Technology
Publisher
Elsevier
School
Centre for Advanced Materials and Manufacturing / School of Engineering
Funders
Shaanxi Innovative Talents Promotion Plan—Shaanxi Youth Science and Technology Star Program (2025ZC-KJXX-94) / Key Research and Development Projects of Shaanxi Province (2023 YBGY-433) / Xi’an Talent Program Young Innovative Talents (XAYC 2023030) / Edith Cowan University (23965)
Copyright
subscription content
First Page
121
Last Page
137
Comments
Zheng, Z., Zhang, Z., Chen, J., Zhang, X., Xu, J., Liu, C., Fu, Y., Zhu, J., Dong, L., & Zhang, L. (2025). Synergistic effects of interstitial elements and TiB to overcome strength-ductility trade-off in titanium matrix composites. Journal of Material Science and Technology, 258, 121–137. https://doi.org/10.1016/j.jmst.2025.09.040