Plastic deformation of single crystals of TiSi2 with the C54 structure Original Research Article

The deformation behavior of single crystals of TiSi2 with the orthorhombic C54 structure has been investigated as a function of crystal orientation in the temperature range from room temperature to 1400 °C in compression. Plastic flow is possible only when slip along <110> on (001) is operative and no other slip systems are observed in the whole temperature range investigated. While plastic flow is observed above 300 °C for as-grown crystals, the onset temperature for plastic flow is lowered considerably down to room temperature when the crystal is prestrained at 1300 °C and then re-deformed at low temperatures. The critical resolved shear stress (CRSS) for (001)<110> slip decreases with increasing temperature, exhibiting a moderate peak (or plateau) in the temperature range from 800 to 1100 °C. The deformation mechanism of TiSi2 is discussed in comparison with those reported for other transition-metal disilicides with the C11b and C40 structures, which are closely related to the C54 structure of TiSi2.