Instrumented indentation of bulk metallic glasses: constant loading rate test vs. constant strain rate test

Abstract

Instrumented indentation tests are applied widely for evaluating localized plastic flow of amorphous alloys. In this study, the plastic flow of bulk metallic glasses (BMGs) at room temperature were investigated using instrumented indentation tests under two different modes of indentation rate: constant loading rate test (0.05 ~ 5 mN/s) and constant strain rate test (0.01 ~ 0.5 s-1). Since strain rate varies during a constant loading rate test and vice versa, it is interesting to compare the mechanical responses obtained from different rate-mode tests. Results are discussed in terms of the influences of testing mode and rate on plastic flow characteristics in BMGs.

This research was supported by the Korea Research Foundation Grant funded by the Korean Government, MOEHRD (Grant # KRF-2006-331-D00273).