A theoretical model based on Hill’s general method is developed in the present study to calculate the flow stress in a cylindrical specimen under axial compression in the presence of friction at the die-specimen interface. Unlike most of the published methods which studied the incipient barreling only, the proposed theoretical model takes the barreled shape of the deforming specimen into account. In order to construct the stress-strain curve, the mean effective strain of the barreled specimen was also calculated on the basis of an assumed velocity field. As the present study shows, the proposed theoretical model provides good results, both in magnitude and in trend, for the prediction of flow stresses in the barreled specimen during the compression test. [S0094-4289(00)00602-2]

Issue Section:
Technical Papers
Keywords:
plastic flow, stress-strain relations, friction, compressive testing
Topics:
Compression, Cylinders, Deformation, Flow (Dynamics), Friction, Stress
1.
Siebel, E., 1923, Stahl und Eisen, Duesseldorf, 43, p. 1295.
2.
Avitzur, B., 1968, Metal Forming: Process and Analyses, McGraw-Hill, New York, pp. 102–111.
3.
Lee
,
C. H.
, and
Altan
,
T.
,
1972
, “
Influence of Flow Stress and Friction Upon Metal Flow in Upset Forging of Rings and Cylinders
,”
ASME J. Eng. Ind.
,
94
, Aug., pp.
775
–
782
.
4.
Ettouney
,
O.
, and
Hardt
,
D. E.
,
1983
, “
A Method for In-Process Failure Prediction in Cold Upset Forging
,”
ASME J. Eng. Ind.
,
105
, pp.
161
–
167
.
5.
Bridgman, P. W., 1952, Studies in Large Plastic Flow and Fracture, McGraw-Hill, New York, pp. 9–86.
6.
Hill
,
R.
,
1963
, “
A General Method of Analysis for Metal-Working Processes
,”
J. Mech. Phys. Solids
,
11
, pp.
305
–
326
.
7.
Lahoti
,
G. D.
, and
Kobayashi
,
S.
,
1974
, “
On Hill’s General Method of Analysis for Metal-Working Processes
,”
Int. J. Mech. Sci.
,
16
, pp.
521
–
540
.
8.
Kobayashi, S., Oh, S. I., and Altan, T., 1989, Metal Forming and the Finite-Element Method, Oxford University Press, Oxford, pp. 78–83.
9.
Chakrabarty, J., 1996, private communications.
10.
Horton, H. L., Ryffel, H. H., and Schubert, P. B., 1959, Machinist’s Handbook, 16th Edition, The Industrial Press, New York, p. 152.
11.
Johnson, W., and Mellor, P. B., 1975, Engineering Plasticity, Van Nostrand Reinhold, London, pp. 110–114.
Copyright © 2000
 by ASME
You do not currently have access to this content.