Microstructure and Mechanical Properties of an Extruded Fe_(30)Ni_(20)Mn_(25)Al_(25) Alloy

摘要

A spinodal alloy, Fe_(30)Ni_(20)Mn_(25)Al_(25), was produced by casting followed by hot extrusion. The microstructure consisted of coherent, 20-30 nm wide rods of alternating body-centered cubic (b.c.c.) and ordered B2 phases aligned along <100>. The room temperature mechanical properties were determined under compression over a range of strain rates. The as-extruded yield strength, which was strain-rate dependent, was ~1400 MPa. Annealing at 550°C led to the precipitation of large unit cell cubic phase and to an increase in hardness. Post-mortem TEM analysis of the compressed specimens identified dislocations having <111> Burgers vectors.