NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Stylus Technique for Direct Verification of Rockwell Diamond Indenters
Published
Author(s)
Jun-Feng Song, F Rudder, Theodore V. Vorburger, J Smith
Abstract
Based on a stylus technique, a microform calibration system was developed at NIST for the direct verification of Rockwell diamond indenters. The least-squares radius and profile deviations, cone angle and cone flank straightness, and the holder axis alignment error can be calibrated with traceability to fundamental measurements. The expanded measurement uncertainties are less than 1/10 of tolerance requirements of calibration-grade Rockwell diamond indenters specified in ASTM and ISO standards. The calibration requirements, instrument setup, calibration and check standards, calibration and uncertainty procedure, and the calibration results are described. Based on this calibration system, the use of the NIST standard-grade Rockwell diamond indenters is also suggested for the establishment of the reference-value scale for a metrology-based Rockwell hardness standard system and for the unification of Rockwell hardness standards.
Proceedings Title
Proceedings of the 9th International Symposium of Hardness Testing in Theory and Practice
Song, J.
, Rudder, F.
, Vorburger, T.
and Smith, J.
(1995),
Stylus Technique for Direct Verification of Rockwell Diamond Indenters, Proceedings of the 9th International Symposium of Hardness Testing in Theory and Practice, Dusseldorf, 1, GE
(Accessed October 18, 2025)