Charpy Interlaboratory Comparison between NIST and the Beijing Institute of Metrology (BIM)

Published

September 12, 2019

Author(s)

Enrico Lucon, Raymond L. Santoyo

Abstract

The Beijing Institute of Metrology (BIM, China) and NIST have participated in an interlaboratory comparison, in which reference Charpy specimens of three energy levels were tested. Each laboratory tested 75 specimens supplied by the other institute, 25 per energy level, at room temperature (21 °C ± 1 °C) and using an impact machine equipped with a 2 mm striker. The results obtained show good to excellent agreement between BIM and NIST, except at the low-energy level (20 J to 25 J), where NIST data obtained using a U type machine were significantly higher than BIM data obtained using a C-type machine. Twenty-five additional low- energy BIM specimens, tested by NIST using a C-type machine, showed excellent consistency with BIM reference data and therefore confirmed that, for low-energy specimens, the configuration of the swinging hammer may affect test results, due to the different stiffness/compliance of the two machine types. A similar, but unexpected, trend was observed for the NIST super-high-energy specimens, and will need to be explained though further investigations.

Citation

Technical Note (NIST TN) - 2061

Report Number

2061

NIST Pub Series

Technical Note (NIST TN)

Pub Type

NIST Pubs

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DOI Link

Keywords

2 mm striker, Charpy reference specimens, C-type hammer, interlaboratory comparison, U type hammer.

Citation

Lucon, E. and Santoyo, R. (2019), Charpy Interlaboratory Comparison between NIST and the Beijing Institute of Metrology (BIM), Technical Note (NIST TN), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://doi.org/10.6028/NIST.TN.2061 (Accessed October 6, 2024)