NIST Recommended Practice Guide: Rockwell Hardness Measurement of Metallic Materials

Published

January 1, 2001

Author(s)

Samuel R. Low III

Abstract

The Rockwell hardness test continues to be applied as a tool for assessing the properites of a product while the tolerances on the acceptable material hardness have become tighter and tighter. Adhering to good practice procedures when performing Rockwell hardness measurements and calibrations is a beneficial step to reducing measurement errors. The purpose of this Guide is to explain the causes of variability in Rockwell hardness test results and to supplenment the information given in test method standards with good practice recommendations. Although this Guide is directed more towards the users of Rockwell hardness having the greatest concern for accuracy in their measurements, much of the information given is also applicable to users that only require test results to be within wide tolerance bands, where high accuracy is not as critical.

Citation

Special Publication (NIST SP) - 960-5

Report Number

960-5

NIST Pub Series

Special Publication (NIST SP)

Pub Type

NIST Pubs

Download Paper

Local Download

Keywords

error, hardness, indentation, indenter, rockwell, standardization, test block, test method, verification

Citation

Low, S. (2001), NIST Recommended Practice Guide: Rockwell Hardness Measurement of Metallic Materials, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=853006 (Accessed October 16, 2025)