Synthesis and Microstructural Characterization of Substoichiometric Ti 2 Al(C x N y ) Solid Solutions and Related Ti 2 AlC x and Ti 2 AlN End‐Members

Ti , TiC , Al and AlN powders were mixed to synthesize Ti 2 Al ( C x N y ) ( x  +  y  < 1) solid solutions, Ti 2 AlC x ( x  < 1) and Ti 2 AlN ‐related end‐members by hot isostatic pressing at 1400°C/80 MPa for 4 h. For the pure carbides, it is demonstrated that single‐phased samples can only be obtained when about 15% of substoichiometry on the carbon site is applied. Such a result likely implies that Ti 2 AlC x can only exist in a narrow range of carbon composition. Ti 2 AlN nitride can be synthesized with y  = 1. Assuming that vacancy content varies linearly from 0 to 0.15 going from Ti 2 AlN to Ti 2 AlC 0.85 in the solid solutions, element concentrations have been calculated to synthesize different solid solutions. Thus, it is demonstrated that single‐phased and fully dense Ti 2 Al ( C 0.23 N 0.71 ), Ti 2 Al ( C 0.45 N 0.45 ), and Ti 2 Al ( C 0.66 N 0.22 ) carbonitrides can be synthesized.