Localized deformation of equal channel angular extruded aluminum

The localized deformation behavior of annealed Al and Al severely deformed by ECAE process was determined by using microindentation test. Using the method proposed by Tabor, the indentation stress-strain curves of annealed Al and as-ECAE deformed Al were constructed, which display similar work-hardening behavior. For annealed Al, the altitude of the indentation stress-strain curves is a function of the indenter size. A master curve then is constructed, which displays different work-hardening behavior. For the ECAE deformed Al, the indentation stress-strain curves are independent of the indenter size, suggesting that the microstructure inside the as-ECAE deformed Al is different from the annealed Al.