Regional Comparisons of National Primary Standards of Hardness According to the Vickers and Brinell Scales

The determination and validation of the calibration capabilities of national metrology institutes is necessary to verify the assessed metrological characteristics of primary standards. Comparisons of national primary measurement standards stimulate a deep and detailed study of the factors affecting measurement uncertainty. The introduction of the calibration capabilities of metrological institutes into the database of the International Bureau of Weights and Measures (BIPM) makes it possible to calibrate measuring instruments recognized by the entire world community. The article presents the results of comparisons of national primary standards of hardness according to the Vickers and Brinell scales of metrological institutes of the countries included in the Euro-Asian cooperation of state metrological institutions (COOMET). Comparisons were carried out within the framework of the activities of the technical committee on mass and related quantities TC 1.6, topic code - 341/RU/05. The procedure for regional key and supplementary comparisons of national primary standards of hardness according to the Brinell and Vickers scales is described. Based on the results of the comparisons, the laboratories participating in the comparisons were recommended values of expanded measurement uncertainties, which can be entered into the database of the International Bureau of Weights and Measures (BIPM).