Abstract
Nanoindentation data reveal interesting behavior in aluminum with various purity levels: 99.9999% (6N), 99.99% (4N), and 99% (2N). Nanoindentation is used to investigate the relationship between the purity level and the mechanical properties at room temperature. Moreover, to clear the differences between microscopic and macroscopic mechanical properties, conventional tensile test and hardness test are performed. It is suggested that the deformation behavior in microscopic scale is different from that in macroscopic scale, and that a perfect crystal is harder than an imperfect crystal. Furthermore, some recovery of the indentation mark is observed in ultrahigh-purity aluminum, caused by the mobility of defects in the sample.
