Effect of annealing temperature on the texture of mechanically alloyed Fe-40at%Al+Y2O3 intermetallic

The results of this study can be summarized as follows: 1) A strong <110> fibre texture develops after extrusion. The preferred grain orientation is due to plastic deformation since the presence of Y2O3 particles inhibits recrystallization, which instead occurs in the same un-reinforced alloy giving rise to the <111> fibre texture. The O.D.F. examination evidences the presence of the <320> texture component of minor intensity. 2) The material is essentially stable if heat treated up to 1373 K and the type of texture does not change. 3) Texture variations are observed after heating at 1473K: along the main fibre axis the [211] direction becomes predominant and a similar re-orientation occurs also in the secondary texture component towards the [032] and [023] directions. 4) After the heat treatment at 1573 K grains of large size cover the whole surface of the samples. The fibre texture completely disappears and the pole figures indicate that the grains have scattered orientations. 5) As shown by TEM observations, the Y2O3 particles coarsen for treatments at temperatures higher than 1373 K and so they are no more able to pin grain boundaries. As a consequence, abnormal grain growth takes place leading to the the texture evolution described above.