Nanostructured Al Powder Obtained by High Energy Ball Milling at Ambient and Cryogenic Temperatures

摘要

High performance nanostructured light metals and alloys are very interesting for replacing conventional heavier materials in many industrial components. High Energy Ball Milling and Cryomilling are useful techniques to obtain nanocrystalline powders. In this work the effect of several milling conditions such as rotation speed, time, ball to powder ratio and temperature on the crystallite and particle size and morphology in pure aluminum are presented. X-Ray Diffraction, Laser Diffraction and Scanning Electron Microscopy are used. High energy ball milling at ambient and cryogenic temperature of Al powders rapidly leads to a nanometer size down to about 35 nm. High ball to powder ratio promotes both low crystallite and particle size. Small crystallite size like 18 nm and particle size as 4 nm were achieved in the most energetic conditions at ambient temperature. Isopropyl alcohol used as liquid media and protective atmosphere has a strong influence on the results depending on the milling temperature of Al.