MATERIALS TESTING, vol.57, no.6, pp.580-584, 2015 (SCI-Expanded)
In this study, pure aluminum powders were turned into bulk material using equal channel angular densification (ECAD)/equal channel angular pressing (ECAP) and further deformed up to 16 passes at 100 degrees C. For comparison, pure aluminum powders were also compacted in a mold without ECAD/ECAP process at the same temperature. The microstructures were characterized using TEM for grain size and shape measurements. In general, the grains were finer in the specimens processed by ECAD/ECAP than in the compacted specimen without ECAD/ECAP process. The high density which is very close to the full density of pure aluminum (2.7 g x cm(-3)) was reached at the second pass of ECAD/ECAP. By the application of ECAD/ECAP process, severe plastic deformation enabled particles to be compacted into fully dense materials at much lower temperatures and shorter times, compared to the conventional sintering process. The ECAD/ECAP process was shown to provide an effective method for producing nano-sized grain and nearly full densification in aluminum powder.