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We present a new class of TiBw/Ti6Al4V composites with a network reinforcement architecture that exhibits a significant creep resistance compared to monolithic Ti6Al4V alloys. Creep tests performed at temperatures between 773 K and 923 K and stress range of 100 MPa-300 MPa indicate both a significant improvement of the composites creep resistance due to the network architecture made by the TiB whiskers (TiBw), and a decrease of the steady-state creep rates by augmenting the local volume fractions of TiBw in the network region. The deformation behavior is driven by a diffusion-controlled dislocation climb process. Moreover, the activation energies of these composites are significantly higher than that of Ti6Al4V alloys, indicating a higher creep resistance. The increase of the activation energy can be attributed to the TiBw architecture that severely impedes the movements of dislocation and grain boundary sliding and provides a tailoring of the stress transfer. These micromechanical mechanisms lead to a remarkable improvement of the creep resistance of these networked TiBw/ Ti6Al4V composites featuring the special networked architecture.Titanium alloys, and in particular titanium matrix composites (TMCs) have been evaluated in board range of aerospace, weapons and sports equipment applications 1-3 . The main rationale behind their use is the high strength-to-weight ratio and high corrosion resistance 4,5 . TMCs have also been used to produce composite monofilament lattice structures 6 and composites with carbon fiber reinforcements for nuclear applications 7 . Quite recently TMCs have also been manufactured via selective laser melting for biomedical applications [8][9][10] . Discontinuously reinforced titanium matrix composites (DRTMCs) have also been developed, and some examples of this class of metal matrix composites are TiB/Ti 11 , TiC/Ti-6Al-4V 12 , (TiB + TiC + La 2 O 3 )/Ti 13 and (Ti 5 Si 3 + TiB)/TC4 14 compounds. Among the various reinforcements adopted for DRTMCs, TiB whiskers (TiBw) are considered to be one of the best because of their high strength and good chemical compatibility with the titanium matrix 15 . Recently, Huang et al. 16 have developed a class of TiBw/Ti6Al4V composite with a network microstructure in which the reinforcements have a designed and tailored network-like distribution, instead of a conventional homogeneous one. These composites show superior high-temperature tensile properties over their traditional TMC counterparts.The understanding and tailoring of the creep performance are preconditions for an effective use of TMCs in structural applications at high temperatures 11,[17][18][19] . The creep behavior mechanisms of traditional TMCs with homogeneous reinforcement distributions have been so far extensively investigated 2,17,20,21 . In general a high volume fraction of the reinforcement can increase the creep resistance, but has detrimental consequences on the room-temperature plasticity and deformability of these composites. TMCs tend to exhibit an improved creep resistance co...

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