OXYGEN DETERMINATION IN ALUMINUM IRON PRE-ALLOYED POWDERS BY NUCLEAR-REACTION ANALYSIS

Oxygen content in aluminium alloys A1-3Fe or Al-8Fe-1Zr (wt%) maked fr om air atomized powders by a sinter-forging process (in the range of 3 20 to 500 degrees C) has been determined by using a Nuclear Reaction A nalysis (N.R.A). The amount of Oxygen, either in pressed compacts or i n hot-forged samples was measured with an accuracy of +/- 15% and foun d to be equal to 1-2 wt%. In fact, during atomization in air and/or th eir subsequent storage, these powders have adsorbed a rather important quantity of oxygen and water vapor leading to the formation of oxides and hydroxides. Only after outgassing over 200 degrees C, Al2O3 is ke pt, which explains differences in oxygen content in pressed or hot for ged samples.