Formation mechanisms and atomic configurations of nitride phases at the interface of aluminum nitride and titanium

Abstract

were formed during cooling. Further diffusion of N atoms into the reaction zone precipitates a chopped fiber-like ␣ 2 -Ti 2 AlN in the matrix of ␥-TiAl, with [110] ␥−TiAl //[1120] 2 −Ti 2 AlN and (111) ␥−TiAl //(1103) 2 −Ti 2 AlN , by substituting N atoms for one-half Al atoms after annealing at 1400°C for 1 h. The released Al atoms, due to the precipitation of 2 -Ti 2 AlN, resulted in an ordered Al-rich ␥-TiAl or Ti 3 Al 5 . Furthermore, the ␣-Ti (Al, N) was nitridized into a lamellar layer (␦-TiN + ␣-Ti) with [110] ␦−TiN //[1120] ␣−Ti and (111) ␦−TiN //(0001) ␣−Ti .