In forming of advanced high-strength steel (AHSS), the temperature increase at die/sheet interface affects the performance of lubricants and die wear. This study demonstrates that finite-element (FE) analysis, using commercially available software, can be used to estimate temperature increase in single as well as in multiple stroke operations. To obtain a reliable numerical process design, the knowledge of the thermal and mechanical properties of the sheet as well as the tools is essential. Using U-channel drawing the thermomechanical FE model has been validated by comparing predictions with experimental results. The effect of ram speed and stroking rate (stroke per minute (SPM)) upon temperature increase in real productionlike operation have been investigated. Deep drawing of CP800 and DP590 sheets in a servodrive press, using an industrial scale die, has been studied. Thinning distribution and temperatures in the drawn part have been investigated in single and multiple forming operations. It is found that temperatures may reach several 100 deg and affect the coefficient of friction (COF). The values of COF under productionlike conditions were compared to that obtained from laboratory experiments. This study illustrates that in forming AHSS, (a) the temperature increase at the die/sheet interface is relatively high and should be considered in process design stage, and (b) the lubricant performance is significantly affected by the ram speed and sheet/die interface temperature during deformation.

References

1.
Altan
,
T.
, and
Tekkaya
,
A. E.
,
2012
, “
Plastic Deformation-Flow Stress, Anisotropy, and Formability
,”
Sheet Metal Forming-Fundamentals
,
ASM International
, Materials Park, OH, pp.
33
52
.
2.
Altan
,
T.
, and
Tekkaya
,
A. E.
,
2012
, “
Electromechanical Servo-Drive Presses
,”
Sheet Metal Forming-Fundamentals
,
ASM International
, Materials Park, OH, pp.
160
180
.
3.
Kim
,
H.
,
Altan
,
T.
, and
Yan
,
Q.
,
2009
, “
Evaluation of Stamping Lubricants in Forming Advanced High Strength Steels (AHSS) Using Deep Drawing and Ironing Tests
,”
J. Mater. Process. Technol.
,
209
(
8
), pp.
4122
4133
.
4.
Pereira
,
M. P.
, and
Rolfe
,
B. F.
,
2014
, “
Temperature Conditions During ‘Cold’ Sheet Metal Stamping
,”
J. Mater. Process. Technol.
,
214
(
8
), pp.
1749
1758
.
5.
Farren
,
W.
, and
Taylor
,
G.
,
1925
, “
The Heat Developed During Plastic Extension of Metals
,”
Proc. R. Soc. London, Ser. A
,
107
(
743
), pp.
422
451
.
6.
Gaard
,
A.
,
Hallback
,
N.
,
Krakhmalev
,
P.
, and
Bergstrom
,
J.
,
2010
, “
Temperature Effects on Adhesive Wear in Dry Sliding Contacts
,”
Wear
,
268
(
7–8
), pp.
968
975
.
7.
Wilson
,
W. R. D.
,
1997
, “
Tribology in Cold Metal Forming
,”
ASME J. Manuf. Sci. Eng.
,
119
(
4B
), pp.
695
698
.
8.
Kim
,
J. H.
,
Sung
,
J. H.
,
Piao
,
K.
, and
Wagoner
,
R. H.
,
2011
, “
The Shear Fracture of Dual-Phase Steel
,”
Int. J. Plast.
,
27
(
10
), pp.
1658
1676
.
9.
Ju
,
L.
,
Patil
,
S.
,
Dykeman
,
J.
, and
Altan
,
T.
,
2015
, “
Forming of Al 5182-O in a Servo Press at Room and Elevated Temperatures
,”
ASME J. Manuf. Sci. Eng.
,
137
(
5
), p.
051009
.
10.
Gutscher
,
G.
,
Wu
,
H. C.
,
Ngaile
,
G.
, and
Altan
,
T.
,
2004
, “
Determination of Flows Stress for Sheet Metal Forming Using the Viscous Pressure Bulge (VPB) Test
,”
J. Mater. Process. Technol.
,
146
(
1
), pp.
1
7
.
11.
Billur
,
E.
,
2013
, “
Fundamentals and Applications of Hot Stamping Technology for Producing Crash-Relevant Automotive Parts
,” Ph.D. thesis, The Ohio State University, Columbus, OH.
12.
Ju
,
L.
,
Mao
,
T.
,
Malpica
,
J.
, and
Altan
,
T.
,
2015
, “
Evaluation of Lubricants for Stamping of Al 5182-O Aluminum Sheet Using Cup Drawing Test
,”
ASME J. Manuf. Sci. Eng.
,
137
(
5
), p.
051010
.
13.
Wilson
,
W. R. D.
,
Hsu
,
T. C.
, and
Huang
,
X. B.
,
1995
, “
A Realistic Friction Model for Computer Simulation of Sheet Metal Forming Processes
,”
J. Eng. Ind.
,
117
(
2
), pp.
202
209
.
14.
Sun
,
D. C.
,
Chen
,
K. K.
, and
Nine
,
H. D.
,
1987
, “
Hydrodynamic Lubrication in Hemispherical Punch Stretch Forming—Modified Theory and Experimental Validation
,”
Int. J. Mech. Sci.
,
29
(
10–11
), pp.
761
776
.
15.
Altan
,
T.
,
Ngaile
,
G.
, and
Shen
,
G.
,
2005
, “
Presses and Hammers for Cold and Hot Forging
,”
Cold and Hot Forging-Fundamentals and Applications
,
ASM International
, Materials Park, OH, pp.
115
140
.
You do not currently have access to this content.