Crystallographic textures in rolled and annealed Fe-Ga and Fe-Al alloys

The feasibility of obtaining 001] preferred texture in polycrystalline Fe₈₅Ga₁₅ and Fe₈₅Al₁₅ magnetostrictive alloys containing 1 mol pct NbC using a low-cost conventional thermomechanical processing approach is shown in this work. Thermomechanical processing conditions examined consisted of a sequence of hot rolling, two-stage warm rolling at 400 °C with intermediate anneal at 900 °C and texture anneal in the temperature range of 900 °C to 1300 °C for time periods up to 24 hours. Textures present prior to and after texture annealing were characterized using orientation imaging microscopy in a scanning electron microscope. In the case of Fe₈₅Ga₁₅ alloy with 1 mol pct NbC, the deformation-induced texture after a two-stage warm rolling consists of mixed {100} 〈110〉 and {111} 〈110〉 type partial textures. Texture annealing of the Fe₈₅Ga₁₅ alloy with 1 mol pct NbC at 1150 °C for 2 hours changes the texture to a predominant texture that is close to {001}〈100〉. On increasing the annealing time to 24 hours, the texture shifts toward {110}〈100〉. While texture anneal at both 1150 °C and 1300 °C produces a 001] or near-001] preferred orientation along the rolling direction in the Fe₈₅Ga₁₅ alloy with 1 mol pct NbC, 1150 °C-24 hour treatment was found to provide the strongest 001] orientation among the conditions examined. Similar trends are observed for the case of Fe₈₅Al₁₅ alloy with 1 mol pct NbC.