The present paper presents a relation between the vickers hardness HV and the loading stiffness C of instrumented vickers indentation of metal substrates. The relation is based on the fact that the nonaxisymmetry of the plastic deformation of the vickers indenter leaves the corners of the indentation imprint at the surface of metal substrates after complete unloading. This relation can transform available HV data for metals to C data. It is also shown that the strain hardening details are important in the estimation of material properties and investigators should be cautions when using power-law strain hardening in all cases.

1.
O’Neill
,
H.
, 1967,
The Hardness of Metals and Alloys
,
Chapman and Hall
,
London
.
2.
Kick
,
F.
, 1885,
Das gesetz der proportionalen widerstande and seine Anwendung
,
Felix
,
Leipzig
.
3.
Giannakopoulos
,
A. E.
,
Larsson
,
P. L.
, and
Vestergaard
,
R.
, 1994, “
Analysis of Vickers Indentation
,”
Int. J. Solids Struct.
0020-7683,
31
, pp.
2679
2708
.
4.
Kese
,
K.
, and
Li
,
Z. C.
, 2006, “
Semi-Ellipse Method for Accounding for the Pile-Up Contact Area During Nanoindentation With the Berkovich Indenter
,”
Scr. Mater.
1359-6462,
55
, pp.
699
702
.
5.
Alcalá
,
J.
,
Barone
,
A. C.
, and
Anglada
,
M.
, 2000, “
The Influence of Plastic Hardening on Surface Deformation Modes Around Vickers and Spherical Indents
,”
Acta Mater.
1359-6454,
48
, pp.
3451
3464
.
6.
Baxevani
,
E. A.
, and
Giannakopoulos
,
A. E.
, 2009, “
The Modified Rockwell Test: A New Probe for Mechanical Properties of Metals
,”
Exp. Mech.
0014-4851,
49
, pp.
371
382
.
7.
Dao
,
M.
,
Chollacoop
,
N.
,
Van Vliet
,
K. J.
,
Venkatesh
,
T. A.
, and
Suresh
,
S.
, 2001, “
Computation Modelling of the Forward and Reverse Problems in Instrumented Sharp Indentation
,”
Acta Mater.
1359-6454,
49
, pp.
3899
3918
.
8.
Tirupataiah
,
Y.
, and
Sundararajan
,
G.
, 1991, “
On the Constrain Factor Accociated With the Indentation of Work-Hardening Materials With a Spherical Ball
,”
Metall. Trans. A
0360-2133,
22
, pp.
2375
2384
.
9.
Lu
,
J.
,
Suresh
,
S.
, and
Ravichandran
,
G.
, 2003, “
Dynamic Indentation for Determining the Strain Rate Sensitivity of Metals
,”
J. Mech. Phys. Solids
0022-5096,
51
, pp.
1923
1938
.
10.
Schwaiger
,
R.
,
Moser
,
B.
,
Dao
,
M.
,
Chollacoop
,
N.
, and
Suresh
,
S.
, 2003, “
Some Critical Experiments on the Strain-Rate Sensitivity of Nanocrystalline Nickel
,”
Acta Mater.
1359-6454,
51
, pp.
5159
5172
.
11.
Carlsson
,
S.
, and
Larsson
,
P. L.
, 2001, “
On the Determination of Residual Stress and Strain Fields by Sharp Indentation Testing. Part II: Experimental Investigation
,”
Acta Mater.
1359-6454,
49
, pp.
2193
2203
.
12.
Williams
,
R. O.
, 1962, “
Stored Energy and Release Kinetics in Head Aluminum, Silver, Nickel, Iron and Zirconium After Deformation
,”
Trans. Metall. Soc. AIME
0543-5722,
224
, pp.
719
726
.
13.
Bailey
,
J. E.
, and
Hirsch
,
P. B.
, 1960, “
The Dislocation Distribution, Flow Stress and Stored Energy in Cold-Worked Polycrystalline Silver
,”
Philos. Mag.
1478-6435,
5
, pp.
485
497
.
14.
Baker
,
I.
, and
Martin
,
J. W.
, 1983, “
Effect of Fine Second Phase Particles on Stored Energy and Recrystallization Kinetics of Cold Rolled Copper Single Crystals
,”
Met. Sci.
0306-3453,
17
, pp.
469
474
.
15.
Durst
,
K.
,
Backes
,
B.
,
Franke
,
O.
, and
Goeken
,
M.
, 2006, “
Indentation Size Effect in Metallic Materials: Modelling Strength From Pop-In to Macroscopic Hardness Using Geometrically Necessary Dislocations
,”
Acta Mater.
1359-6454,
54
, pp.
2547
2555
.
16.
Aravas
,
N.
,
Kim
,
K. S.
, and
Lekie
,
F. A.
, 1990, “
On the Calculations of the Stored Energy of Cold Work
,”
ASME J. Eng. Mater. Technol.
0094-4289,
112
, pp.
465
470
.
17.
Tabor
,
D.
, 1951,
The Hardness of Metals
,
Clarendon
,
Oxford, UK
.
18.
Giannakopoulos
,
A.
, 2008, unpublished results.
You do not currently have access to this content.