Effect of indentation size on strain rate sensitivity of zirconia ceramics by nanoindentation

In this paper, nanoindentation test of zirconia ceramics was carried out under different strain rates by continuous stiffness measurement (CSM) technique at room temperature. This work aimed at studying the influence of indentation size effect (ISE) on strain rate sensitivity (SRS). The results showed that the contact stiffness increased almost linearly with the depth of the indentation. Under different strain rates, the contact stiffness and elastic modulus remain basically unchanged, but the hardness increases with the increase of the strain rate. The SRS exponent m is strongly dependent on the indentation depth. A calculation method for nano-hardness without ISE was proposed by detecting the relationship between hardness and indentation depth.