Microstructures and Properties of the Mechanically Alloyed Intermetallic-Dispersion-Strengthened Al Alloys

Abstract

The mechanical alloying process has been used to produce intermetallic-dispersion-strengthened Al alloys. While the mixing of elemental powders precedes the milling operation in a conventional mechanical alloying method, the mixing method of pre-fabricated intermetallic powders with AI powders has been suggested in this study. Dispersoid intermetallic powders have been made by pulverizing as-arc-melted tetragonal DO_(22)-, DO_(23)-structured A₃(Ti,V,Zr) and cubic Ll₂-structured Al_(66)Mn_9(Ti,Zr)_(25), monolithic compounds. Intermetallic dispersoids in Al alloys found to be stable after the heat-treatment at 425℃ up to 400 hours and overall, specimens maintained original microstructures with a fine distribution of intermetallic compounds. Due to the fine and stable dispersion, alloys showed high compressive yield stress levels at room and elevated temperatures.