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Calibration Reproductibility Test for NIST's No. 3581 Standard Rockwell Diamond Indenter



Jun-Feng Song, Samuel R. Low III, A Zheng


Standard Rockwell diamond indenter plays an important role for a worldwide unified Rockwell hardness scale.  In 1994, NIST established a microform calibration system with sufficiently small calibration uncertainty for the calibration of standard Rockwell indenters.  In 1995, NIST established a group of Rockwell diamond indenters characterized both by high geometrical uniformity and hardness performance uniformity.  One of them, No. 3581, was selected as the NIST s primary Rockwell diamond indenter for the calibration of NIST s Standard Reference Material (SRM) Rockwell C hardness blocks.  This indenter was re-calibrated in 1997 and 2005.  The calibration results showed high stability for the microform geometry of the NIST s standard Rockwell diamond indenter, as well as the high calibration reproducibility for the NIST s microform calibration system.
Proceedings Title
Proceedings of XVIII IMEKO World Congress
Conference Dates
September 17-22, 2006
Conference Location
Rio de Janeiro, BR
Conference Title
IMEKO World Congress


diamond indenter, HRC, microform calibration, reproducibility, Rockwell hardness, traceability


Song, J. , Low, S. and Zheng, A. (2006), Calibration Reproductibility Test for NIST's No. 3581 Standard Rockwell Diamond Indenter, Proceedings of XVIII IMEKO World Congress, Rio de Janeiro, BR (Accessed April 21, 2024)
Created January 1, 2006, Updated February 19, 2017