Metrological characterization of the Primary Hardness Standard Machine and Gal-Vision Measuring System realised by LTF for NPL (India)

The work consists in the metrological characterization of the Primary Hardness Standard Machine (PHS Machine) and Gal-Vision Measuring System realized by LTF S.p.A. for the National Physical Laboratory (NPL), in India. The work described in the report was carried out in January and February 2007, by the Istituto Nazionale di Ricerca Metrologica (INRIM) of Italy (formerly Istituto di Metrologia "G. Colonnetti" (IMGC) of the National Research Council (CNR)) at LTF laboratory in Antegnate (BG), Italy. PHS Machine has been realized by LTF with the INRIM know-how. The Gal-Vision measuring system derives from the measuring system developed in IMGC, now used in INRIM hardness laboratory, based on the CNR patent algorithm. The metrological characterizations consists in the direct and indirect verification of the PHS machine; in the direct verification, the main verified parameters are the forces generated by the PHS machine, the depth measuring system and the geometry of the indenters. The indirect verification consists in the comparison of the Whole performances of machine and measuring system (including indenter performances with the so called “National Indenters”) and in the comparison of the hardness scales generated by the PHS machine with the national scales maintained by INRIM