MICROSTRUCTURE AND TENSILE DEFORMATION BEHAVIOR OF A NANOSTRUCTURED Al-Fe BASED ALLOY

초록

The microstructure and tensile deformation behavior at room temperature were investigated using Al-8Fe-2Mo-2V-1Zr (wt%) alloys produced by spray forming and subsequent hot extrusion. Also, warm rolling at 423 K was employed to the extruded material in order to control microstructure. Tensile test was carried out in air at room temperature and at strain rates from 1x100 s-1 to 1x10-4 s-1. The microstructure of extruded sample was composed of equiaxed grain structure of about 500 nm with very fine (about 50nm in size) dispersoids including an Al-Fe based intermetallic phase. Warm rolling accelerated an occurrence of dispersoids less than 20 nm. The results of tensile test revealed that the yield strength of the rolled sample increases with increasing strain rate, on the other hand, that of the extruded sample is almost insensitve to strain rate. Elongation of the rolled sample was higher than that of the extruded sample at a given strain rate. Maximum elongation of 19% was obtained for the rolled sample deformed at a strain rate of 10-3/s with a steady-state flow.