Possibilities for minimising uncertainty of dissimilar materials gauge blocks calibration by mechanical comparison

Mechanical comparison calibration of gauge blocks with dissimilar materials at the highest level is not wide spread because bigger national laboratories tend to calibrate non-steel gauge blocks with reference gauge block of like material. For smaller laboratories this is not viable economically due to the high costs of reference gauge block sets. Therefore, steel reference sets are used for calibrating gauge blocks from other materials. Lack of knowledge about material properties is causing a significant rise in calibration uncertainty. In order to improve best measurement capabilities, we have performed extensive research on gauge block material behaviour. For this purpose we have bought sample gauge blocks from all leading producers and evaluated their influences on the uncertainty budget, based on experimental measurements.The uncertainty budget of gauge blocks with dissimilar materials mechanical calibration, as well as the results of analytical and experimental research, is presented in this paper in detail. Significantly smaller uncertainty of gauge block calibration of dissimilar materials is achieved.

► Analytical and experimental research on uncertainty components of mechanical calibration of gauge blocks is presented.
► Calibration uncertainty analysis for the case of dissimilar materials gauge blocks.
► Our calibration uncertainties are compared to CMCs of 49 national metrology institutes.