1.1 This practice defines the basic steps of Instrumented Indentation Testing (IIT) and establishes the requirements, accuracies, and capabilities needed by an instrument to successfully perform the test and produce the data that can be used for the determination of indentation hardness and other material characteristics. IIT is a mechanical test that measures the response of a material to the imposed stress and strain of a shaped indenter by forcing the indenter into a material and monitoring the force on, and displacement of, the indenter as a function of time during the full loading-unloading test cycle. 1.2 The operational features of an IIT instrument, as well as requirements for Instrument Verification (Annex A1), Standardized Reference Blocks (Annex A2) and Indenter Requirements (Annex A3) are defined. This practice is not intended to be a complete purchase specification for an IIT instrument. 1.3 With the exception of the non-mandatory Appendix X4, this practice does not define the analysis necessary to determine material properties. That analysis is left for other test methods. Appendix X4 includes some basic analysis techniques to allow for the indirect performance verification of an IIT instrument by using test blocks. 1.4 Zero point determination, instrument compliance determination and the indirect determination of an indenter’s area function are important part