A procedure for extracting primary and secondary creep parameters from nanoindentation data

• A methodology is presented for extraction of creep parameters from indentation data.
• It is shown that primary creep often exerts a strong influence on the behaviour.
• An explanation is provided of why a currently-common methodology gives poor results.

A methodology is presented for the extraction of creep parameters from nanoindentation data – i.e. data obtained from an indentation system with a high resolution displacement measuring capability. The procedure involves consideration of both primary and secondary creep regimes. The sensitivities inherent in the methodology are explored and it is concluded that, provided certain conditions are satisfied, it should be reasonably robust and reliable. In contrast to this, it is also shown that the methodology commonly used at present to obtain (steady state) creep parameters is in general highly unreliable; the effects responsible for this are identified.