Size effect of plasticity of Ti₂AlNb alloy: an in situ micro-pillar compression study

Abstract Ti 2 AlNb alloys have attracted extensive research due to their critical role in the lightweight and high-performance development of aerospace engines. This study investigates in situ compression experiments on single-crystal Ti 2 AlNb alloy micro-pillars at the micro scale. The results reveal that at room temperature, the B2 matrix phase predominantly governs plastic slip, while the O phase impedes dislocation movement, enhancing the material’s strength. Additionally, a “smaller is stronger” size effect was observed by comparing specimens of different sizes.