Dynamic compression behavior of multilayered titanium matrix composites

Multilayer structured titanium matrix composites consisting of pure Ti layers and TiB reinforced Ti-6.5Al-2Zr-1Mo-1V (TA15) composite layers were fabricated through powder metallurgy. The mechanical property and deformation behavior of the composite during dynamic compressions (with strain rates ∼103 s−1) and quasi-static compression (1 × 10−3 s−1) were investigated. The compressive flow stress was improved by nearly 200 MPa under dynamic conditions compared with the quasi-static one. Both the pure Ti layer and the TiB/TA15 layer were deformed during dynamic compression, but the deformation was non-uniform. The deformation of the pure Ti layer was higher than the TiB/TA15 layer, which resulted in a concentration of strain near the layer interface. In dynamic conditions, increasing strain rate led to TiB multi-fracture and TiB-TA15 matrix decohesion. In both the dynamic and quasi-static conditions, {101¯2} and {112¯2} twins were generated in the pure Ti layer, while the formation of the {112¯2} twin was inhibited in the TA15 matrix. Compared with the quasi-static loading condition, dynamic compression promoted the formation of the {112¯1} twin in both the pure Ti layer and the TA15 matrix.