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Charpy Machine Verification: Limits and Uncertainty



Jolene Splett, Christopher N. McCowan, Chih-Ming Wang


The purpose of this document is to clarify some issues pertaining to uncertainty statements and the ASTM E 23 limits used in the Charpy machine verification program. We explain some of the distributional subtleties associated with uncertainty and ultimately relate these to the ASTM limits.
Special Publication (NIST SP) -


absorbed energy, Charpy V-notch, impact test, pendulum impact test, uncertainty, verification testing.


Splett, J. , McCowan, C. and Wang, C. (2008), Charpy Machine Verification: Limits and Uncertainty, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed April 14, 2024)
Created August 31, 2008, Updated October 12, 2021