Microscale investigation of perovskite-Ti3AlC strengthening and plastic deformation in high niobium containing TiAl alloys

作者：Li, Mingao^*; Xiao, Shulong^*; Xu, Lijuan; Tian, Jing; Chen, Yuyong

来源：Journal of Alloys and Compounds, 2021, 857: 157563.

DOI：10.1016/j.jallcom.2020.157563

• TiAl alloys
• Plastic deformation
• Perovskite-Ti3AlC
• Dislocation
• Twinning

The precipitated-phase strengthening caused by dispersive perovskite-Ti3AlC could strengthen TiAl alloys. In present study, it has been found that perovskite-Ti3AlC would also contribute to better plastic deformation and higher elongation of high niobium containing TiAl alloys. Dislocations gliding and twinning mechanism during the plastic deformation and the coherent relationship between the perovskite-Ti3AlC and the neighboring matrix phase have been revealed by transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). Diffraction patterns and high-resolution images indicate the ordinary dislocation 1/2 < 1<(1)over bar>0], the Shockley dislocation 1/6 < <(12)over bar>1] and the twinning <112>{111} appearance within Ti3AlC, accompanied by atomic shuffling and shortrange diffusion. Especially, the nano-twin <112>{111} would absorb partial Shockley dislocation and accommodate parts of dislocations, which play an important role for excellent mechanical properties of high niobium containing TiAl alloys.

• 单位
  重庆理工大学; harbin inst technol