Stable nanoparticles dispersion induced an unprecedented high strength in a bulk W-TiC alloy

The introduction of nano-scale second-phase particles with high thermal stabilities is expected to solve the dilemma of insufficient strength of metallic materials. In this work, an unprecedented high tensile strength of 1.59 GPa at room temperature is obtained in a representative W-TiC system. We focused on the structure and atomic bonding of TiC/W interface to explore the origin of its stability through high-resolution TEM observation and ab initio calculation. Results reveal that strong covalent bonding between W and C atoms and a low-energy semi-coherent interface with Nishiyama-Wassermanm orientation relationship between TiC and W matrix lead to highly stable and refined TiC particles (∼29 nm) that are responsible for a significant strengthening effect. The present study highlights the importance of interface bonding and stability to achieve fine dispersed nanoparticles for high strength in W materials, and paves the way for high-performance metallic materials through regulation of interface structure and atomic bonding.