A Study on the Characteristics of Amorphous TiAl by P/M Processing

Chang-Suk Han, Seung-Jin Jeon
2016 Journal of the Korean Society for Heat Treatment  
The P/M processing of titanium aluminide using amorphous TiAl is developed by which it is possible to overcome inherent fabricability problems and to obtain a fine microstructure. A high quality amorphous TiAl powder produced by reaction ball milling shows clear glass transition far below a temperature at the onset of crystallization in differential scanning calorimetry above a heating rate of 0.05 K/s. We obtained a fully dense compact of amorphous TiAl powders, encapsulated in a vacuumed can,
more » ... via viscous flow by hot isostatic pressing (HIP). Isothermally annealing of HIP'ed amorphous compact under a pressure of 196 MPa shows a progressive growth of γ-TiAl phase with α 2 (Ti 3 Al), which is characterized by increasing sharpness of X-ray peaks with temperature. Fully dense HIP'ed compact of titanium aluminide TiAl shows a high hardness of 505 Hv, suggesting strengthening mechanisms by sub-micron sized grain of γ-TiAl and particle-dispersion by second phase constituent, α 2 .
doi:10.12656/jksht.2016.29.2.51 fatcat:bmjb4ykq2bad3pkl3on6e3lch4