J.L. Nascimento, F.S. Pires, A.C. Rocha, I.M.V. Caminha
The aim of this work is to correlate the homogeneity of the microstructure of two certified hardness standard blocks, both with the same hardness value range, with its uniformity hardness values. In order to identify the morphological characteristics of the blocks studied, as grain size distribution, an automatic image analysis system with software based on ASTM E112 and ASTM E1382 standards was employed. The hardness measurements were carried out in industrial hardness tester machine, in three different regions of the blocks. The results obtained for both blocks showed that, for the regions...
Joint International Conference on Force, Mass, Torque, Hardness and Civil Engineering Metrology in the age of globalization
· TC5
· 2002
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P. Neumaier, G. Michalzik
The load/indentation depth method has received broad acceptance both in quality control and in research and product development for characterizing the mechanical behavior of thin coatings and also of small and smallest material areas. Continuous high-resolution recording of test load and indentation depth for the full test cycle (loading and unloading) is used in a variety of ways in particular for test loads in the microhardness range. Contributing factors to its acceptance were the greater information content of the measurement results, the operator-independent test procedure and the...
Joint International Conference on Force, Mass, Torque, Hardness and Civil Engineering Metrology in the age of globalization
· TC5
· 2002
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S. Tagaki, K. Hattori, Y. Seino, H. Nakano
To investigate the influence of geometric error of indenter tip in nano-indentation test, direct measurement of indenters and analyses of indentation process are carried out. Geometry of indenter tip is measured with a scanning probe microscope and geometrical parameters such as face angles, tip radius and truncation length are calculated. Based on these results, the models for the finite element analyses are created. Analyses of indentation processes into a metal sample are carried out and the influence of tip geometry is discussed.
Joint International Conference on Force, Mass, Torque, Hardness and Civil Engineering Metrology in the age of globalization
· TC5
· 2002
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K. Hattori, S. Takagi, Y. Seino, H. Nakano
We have developed an heterodyne laser interferometer system to measure the indenter displacement of instrumented indentation at nano-/micro- ranges. The developed interferometer was applied to measure the displacement of an commercial type indentation tester. The interferometer system and the tester was set on the different anti-vibration systems. So the main difficulty of this measurement was how to got rid of the relative vibration effect. We designed the system as that the reference points of the system is set to the displacement measurement mirrors on the testers. The total stability of...
Joint International Conference on Force, Mass, Torque, Hardness and Civil Engineering Metrology in the age of globalization
· TC5
· 2002
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M. Tsujii, F. Koshimizu, E. Furuta, K. Kojima, H. Hayashi, H. Ishida
The calibration device capable of performing direct verification of both test force & indentation depth, which are fundamental elements of a Rockwell type hardness tester, was developed. This device can also carry out verification of operating conditions. In this paper, the examples of uncertainty of hardness calculated, based on uncertainty of each element, using this device are shown and the calibration results on the conventional testing machine calibrated by the standardized Rockwell hardness testing machine, which has been used at Akashi Corp., are also shown.
Joint International Conference on Force, Mass, Torque, Hardness and Civil Engineering Metrology in the age of globalization
· TC5
· 2002
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J. Song, S. Low, L. Ma
The form deviations of Rockwell diamond indenters can cause significant differences in Rockwell hardness readings. In order to control that effect, tolerances for form error deviations of Rockwell diamond indenters have been specified in both the American Society of Testing and Materials (ASTM) and the International Organization for Standardization (ISO) standards. In this paper, experimental data on the effects of form deviations of Rockwell indenters are analyzed. Finite Element Analysis (FEA) is used to simulate the effect of form deviations on HRC readings. Theoretical analyses are...
Joint International Conference on Force, Mass, Torque, Hardness and Civil Engineering Metrology in the age of globalization
· TC5
· 2002
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A.C. Vidal, A.R. Martins, I.M.V. Caminha, A. da Cunha Rocha, S.P. Oliveira
In the present work, the influence of thickness variation and of the microstructural aspects on the hardness uniformity of Rockwell B standard blocks is discussed. In order to correlate the results, two different heat treatments were performed on the steel employed to manufacture the standard blocks. Three different thickness ranges were studied for each of the two heat treatments conditions applied to the standard blocks material. The microstructural characteristics were studied by means of optical microscopy. The hardness measurements were carried out in hardness testing machines belonging...
Joint International Conference on Force, Mass, Torque, Hardness and Civil Engineering Metrology in the age of globalization
· TC5
· 2002
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S.R. Low
Characteristics of the empirically developed Rockwell hardness test make it difficult to determine measurement uncertainty using methods based on mathematical models describing the relationship between the measurand and the influence quantities. An empirical approach to determining Rockwell hardness uncertainty has been developed, which provides a method based on the familiar procedures and practices of Rockwell hardness testing laboratories. The approach views the hardness machine and indenter as a single measuring device, and considers uncertainties associated with the machine...
Joint International Conference on Force, Mass, Torque, Hardness and Civil Engineering Metrology in the age of globalization
· TC5
· 2002
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G. Barbato, G. Brondino, M. Galetto, G. Vicario
The Instrumented Indentation Test is based on simultaneous recording of force and indentation depth, obtained during test cycle. The force-depth curve, describing the indentation pattern, is typically formed by two parts having the “zero-point” in common, i.e. the first contact point between the indenter and the surface of test piece. The zero-point determination is a crucial aspect for Martens Hardness evaluation, so that relevant ISO standard suggests to estimate it by extrapolation of polynomial fitted functions. In this paper a new model, based on a segmented function, is proposed. This...
Joint International Conference on Force, Mass, Torque, Hardness and Civil Engineering Metrology in the age of globalization
· TC5
· 2002
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A. Liguori, A. Germak, G. Gori, E. Messina
The paper describes the GALINDENT system that LTF – Galileo Hardness Testing Department, in co-operation with the Institute of Metrology "G. Colonnetti", has developed for the geometrical verification of Rockwell, Vickers diamond indenters, as prescribed by ISO Standards. This system consists of two instruments: an Interferometric Sine-Bar, for angular, straightness and flatness measures and a Rotary Table, for the verification of the spherical tip of Rockwell indenters. These two devices can be set up in one workstation, interfaced with the same computer for data analysis. A software...
Joint International Conference on Force, Mass, Torque, Hardness and Civil Engineering Metrology in the age of globalization
· TC5
· 2002
· Download