Hostname: page-component-8448b6f56d-t5pn6 Total loading time: 0 Render date: 2024-04-23T23:47:38.979Z Has data issue: false hasContentIssue false

The influence of geometrical tolerances of Vickers indenter on the accuracy of measured hardness

Published online by Cambridge University Press:  26 September 2012

M. El-Sherbiny
Affiliation:
Faculty of Engineering, Cairo University, Gamaet El Qahera St. Giza, Giza, Egypt
R. Hegazy*
Affiliation:
National Institute for Standards (NIS), 136 Tersa St., Mahatet El Matbaa, EL HARAM, Cairo, Egypt
M. Ibrahim
Affiliation:
National Institute for Standards (NIS), 136 Tersa St., Mahatet El Matbaa, EL HARAM, Cairo, Egypt
A. Abuelezz
Affiliation:
National Institute for Standards (NIS), 136 Tersa St., Mahatet El Matbaa, EL HARAM, Cairo, Egypt
*
Correspondence: rihamhegazy@yahoo.com
Get access

Abstract

This paper reports work carried out to determine the influence of the Pyramidal indenter geometrical errors and tolerances on the accuracy of Vickers hardness measurements. The angle between the opposite faces and line of conjunction of nine indenters were measured by the optical comparator. The influence of the indenter geometry on the hardness accuracy is investigated. Three calibrated reference hardness test blocks were used to check the Vickers hardness test using the nine selected indenters. The results show that the geometrical error of the indenters (specially the angles) considerably affects the accuracy of the hardness measurement. Finite element analysis of the indentation process into metallic test pieces was conducted. Comparison of the experimental results with the numerical findings was discussed. Errors in the experimental values are correlated with measured tolerances in the angles between faces.

Type
Research Article
Copyright
© EDP Sciences 2012

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

J.G. Wood, J. Cotter, P.J. Nash, Hardness testing – A survey of Rockwell C scale diamond indenters, NPL Report MOM 40, 1980
G. Barbato, S. Desogus, A. Germak, Report on the results obtained in the comparison of the HRC scales maintained at ETCA, IMGC and MPA NRW, Rapporto Tecnico Interno R 382, IMGC, Torino, 1994
R.S. Marriner, J.G. Wood, Investigation into the measurement and performance of Rockwell C diamond indenters, Metallurgia 87 (1967)
G. Barbato, S. Desogus, A. Germak, The development of hardness scales in Europe, Measurement Science conference (Anaheim, CA, 1992)
P. Key, P. Soardo, The European cooperation on calibration testing and certification, Proc. of cooperation in metrology equivalence of the national standards dissemination of SI units, Torino, Italy, 1992, pp. 62–85
J.G. Wood, J. Cotter, Performance predictions of Rockwell indenters, NPL Report MOM 73, 2000
J.G. Wood, J. Cotter, Performance predictions of Rockwell indenters, NPL Report MOM 73, 1999
J.F. Song, S. Low, D. Pitchure, A. Germak, S. DeSogus, T. Polzin, H.Q. Yang, H. Ishida, Establishing a common Rockwell hardness scale using geometrically calibrated standard diamond indenters, Proc. XIV IMEKO World Congress, Tampere, Finland, 1999
Song, J.F., Low, S., Pitchure, D., Germak, A., DeSogus, S., Polzin, T., Yang, H.Q., Ishida, H., Barbato, G., Establishing a world-wide unified Rockwell hardness scale with metrological traceability, Metrologia 34, 331342 (2002) CrossRefGoogle Scholar
J.F. Song, T.V. Vorburger, Standard grade Rockwell diamond indenters – A key to a worldwide unified Rockwell hardness scale, Proc. of National Conference of Standard Laboratories (NCSL, CA, 1996), pp. 403–417
H. Czichos, Springer Handbook of materials measurements methods (Springer, 2006)
L. Brice, Uncertainty in hardness measurements, NPL Report CMAM 87, 2003
L. Brice, The influence of indenter characteristics on hardness measurements, XVII IMEKO World Congress Metrology in the 3rd Millennium, Dubrovnik, Croatia, 2003
Petrík, J., The influence of the ball on the Brinell hardness Tester calibration, Mapan – Journal of Metrology Society of India 23, 197205 (2008) Google Scholar
ISO/CD 5607-1, Metallic materials-Vickers hardness test-test method, 2005
O.C. ZienKiewicz, The finite element method, 5th edn., Solid mechanics (1999), Vol. 2