Abstract
CSIR-National Physical Laboratory (CSIR-NPL) is the National Metrological Institute (NMI) of India, which has the mandate for the realization of SI units of measurements and dissemination of the same to the user organizations. CSIR-NPL has established a hardness standardizing machine for realizing the Vickers hardness scale as per ISO 6507-3 standard for providing national traceability in hardness measurement. Direct verification of the machine has been carried out by measuring the uncertainty in the generated force, the indenter geometry and the indentation measuring system. From these measurements, it is found that the machine exhibits a calibration and measurement capability (CMC) of ±1.5% for HV1–HV3 scales and ±1.0% for HV5–HV50 scales and ±0.8% for HV100 scale.
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Acknowledgement
The authors are grateful to Director, National Physical Laboratory for his encouragement and permission to publish the work. The authors are also thankful to Ex-Scientist G of NPL for his suggestions.
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Titus, S.S., Vikram, Girish et al. Metrological Characterization of the Vickers Hardness Primary Standard Machine Established at CSIR-NPL. J. Inst. Eng. India Ser. C 99, 315–321 (2018). https://doi.org/10.1007/s40032-017-0359-9
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DOI: https://doi.org/10.1007/s40032-017-0359-9