Evaluation of Lubricants for Stamping of Al 5182

Transcription

Long Ju
School of Mechanical Engineering,
University of Science and Technology Beijing,
30 Xueyuan Road,
Haidian, Beijing 100083, China
e-mail: [email protected]
1
Tingting Mao
2
Center for Precision Forming,
The Ohio State University,
339 Baker Systems,
1971 Neil Avenue,
Columbus, OH 43210
43
5
Julio Malpica
Honda Engineering of North America, Inc.,
24000 Honda Parkway,
Marysville, OH 43040
Taylan Altan1
Center for Precision Forming,
The Ohio State University,
339 Baker Systems,
1971 Neil Avenue,
Columbus, OH 43210
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
Evaluation of Lubricants
for Stamping of Al 5182-O
Aluminum Sheet Using Cup
Drawing Test
Lubricants are necessary to avoid adhesion, galling, and scratching in aluminum stamping processes. In this study, various lubricants, including dry lubes and wet lubes, were
evaluated using cup drawing test (CDT) for stamping of Al 5182-O aluminum sheets. The
effects of surface texturing, with electro-discharge texturing (EDT) and mill finish (MF),
on the friction behavior were also investigated. Furthermore, the methodology to evaluate the performance of lubricants was established based on (a) maximum applicable
blank holder force (BHF) and (b) draw-in length in flange or flange perimeter of formed
cups. Finite element (FE) simulations were carried out to determine the coefficient of
friction (CoF) at tool–workpiece interface during deep drawing under different lubrication conditions. Flow stress data of Al 5182-O material were obtained using viscous pressure bulge (VPB) and tensile tests. In this study, it was confirmed that, in forming Al
5182-O, dry film lubricants have better lubricity than wet lubricants. A better lubrication
condition was found with EDT surface texture. [DOI: 10.1115/1.4030750]
Keywords: aluminum stamping, lubrication, surface texturing, finite element analysis
surface finishes: MF and EDT [3]. By using 2D and 3D measurements, it is reported that EDT can provide a higher closed void
Lightweight materials, such as aluminum alloys, are increasarea ratio in the sheet surface to ensure a better lubricant distribuingly used in sheet metal forming of automotive parts. In forming
tion and transport than MF. As a result, a lower CoF could be
aluminum alloys, adhesive wear and galling, due to insufficient
achieved by using EDT [9,10]. From a microscopic scale point of
lubricant, can greatly affect the quality of stamped parts [1]. The
view, the characterization of the asperities and valleys on the die
right lubricant can reduce or even avoid failures associated with
and workpiece surfaces could provide more reasonable expiations
wrinkling and premature fracture, thus increasing the process winfor many tribological phenomena in sheet metal forming [11]. For
dow [2]. There are mainly two types of lubricants used for alumia given tool, sheet material, and surface finish, the friction is also
num sheet metal forming: dry-film lubricants and mineral oil
affected by rolling direction of the sheet, sliding direction of the
based lubricants. Lubricants used in stamping lines are mainly
contacts [9] and the contact pressure as well as relative velocity
based on mineral oils. They have good deep drawing performance and interface temperature [12]. The well-known Stribeck curve
and can be used in forming complex parts, such as inner door pan- was applied to describe the dependency of friction on contact
els with most metals [3]. In recent studies, dry film lubricants
pressure, sliding velocity, and dynamic viscosity of the lubricant
have been used in forming to avoid scratching and galling of the
[13]. From the experimental study on the strip drawing of Al
tools [4,5]. Regarding the evaluation of various lubricants, twist
sheets, adhesive wear was found to occur as a result of local peak
compression test [6], deep drawing test (including CDT [7], and
stress and temperature rise [1].
strip drawing test [8]) are found to be most practical testing methIn the present study, a methodology was established to evaluate
ods. Using inverse analysis and the measured data from CDT
the performance of different lubricants for stamping of Al 5182-O
tests, the CoF can be estimated with FE simulation. At the Center
sheets. Selected lubricants were evaluated by using CDT in a
of Precision Forming (CPF), it was concluded that, compared with
hydraulic press. The effects of two different surface texturing, MF
other lubricant testing method, the CDT can emulate the “nearand EDT, were investigated in detail. The specific objectives are
production” conditions well [7]. It should be noted that the present
to: (a) select the lubricants that perform best in drawing of alumitesting method applies primarily for deep drawing operations.
num sheet 5182-O, (b) compare the friction behavior between MF
However, in conducting FE simulations of stamping operations,
surface and EDT surface, and (c) determine the CoF at the
for practical reasons, only one average value of CoF is used.
tool–workpiece interface under various lubrication conditions.
Thus, the CoF obtained from the CDT can be used in FE analysis
The obtained CoF for selected lubricants can be used as input into
of stamping.
FE simulations of stamping with complex geometries used in
The surface finish of the sheet also affects the lubrication durautomotive production, such as hoods, decklids, and doors.
ing forming. Aluminum sheet is commercially available in two
1
Introduction
1
Corresponding author.
Contributed by the Manufacturing Engineering Division of ASME for publication
in the JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING. Manuscript received
January 14, 2015; final manuscript received May 19, 2015; published online xx xx,
xxxx. Assoc. Editor: Blair E. Carlson.
2
Experimental Procedures
2.1 Sheet Materials. In the present study, the sheet materials
were characterized by both standard tensile test and VPB test. The
tensile tests were conducted in rolling, diagonal, and transverse
Journal of Manufacturing Science and Engineering
CCopyright V 2015 by ASME
ID: asme3b2server Time: 19:39 I Path: D:/ASME/Support/XML_Signal_Tmp/AS-MANU150085
MONTH 2015, Vol. 00 / 000000-1
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
J_ID: MANU DOI: 10.1115/1.4030750 Date: 6-June-15
Stage:
Page: 2
Total Pages: 9
PROOF COPY [MANU-15-1035]
Table 1 Mechanical properties of Al 5182-O from tensile tests
(conducted by Honda R&D)
Fig. 1 Flow stress curves obtained from tensile test and VPB
test
74
2.2 Lubricant Samples and Surface Textures. In this study,
75
14 lubricants were evaluated. All the lubricants are used as
76
received, except lubricant I, which had to be diluted with water in
77
78
the ratio of 1:3 (lubricant/water). The coating weight applied on
79
the blank was 1 g/m2 for all lubricants. The details of lubricant
80
type and application method are summarized in Table 2. The time 81
82
period, from the application of a wet lubricant until the test is
83
completed, was approximately 5 min.
84
Application of lubricants on the blank was done by using a pip85
ette and draw down bar #0. Each lubricant was spread all over the 86
87
blank surface on both sides uniformly. Three drops of the lubri88
cant were applied on each side of blank to achieve a coating
89
90
weight (1.0 g/m2 6 0.3 g/m2). Since it is difficult to manually
91
apply the dry film lubricant in the laboratory scale, some of the
92
dry film lubricants were required to be precoated by the lubricant
93
94
companies with the same amount as wet lubricants. The coating
weight/amount was verified by measuring a few samples using the 95
96
laboratory balance before and after lube application. Additionally, 97
98
the applied lubricant thickness was verified by using a portable
99
tool (Microderm CMS). The coating weight measured by Micro100
derm CMS tool was around 1.24 g/m 2, which was within the range 101
102
of the coating requirement, recommended by the lubricant
103
suppliers.
104
The 5182-O aluminum sheets were available with two different
surface texturing, MF and EDT. Three-dimensional view of EDT
surface texture measurement, conducted by Honda Engineering, is
shown in Fig. 2. In order to have better understanding about the
difference in the surface topography, the roughness parameters,
Ra and Rz, were compared in Table 3. It can be seen that the EDT
texture provide higher deviation values and the pocket structure
on the surface can definitely effect the lubricated contacts.
directions, respectively. Table 1 lists the material properties
obtained from the tensile tests. VPB test, developed by CPF, could
provide higher strain values under biaxial state of stress [14].
Figure 1 shows the flow stress curves obtained from the two tests.
It can be seen that the flow stress could be obtained at true strain
of about 0.5 with the VPB test.
2.3 Principles of CDT–CDT. The cup drawing process is
extensively used to evaluate the performance of lubricants. The
schematic of CDT is illustrated in Fig. 3. In cup drawing, the most
severe friction takes place at the flange and die corners.
Sample
Ultimate tensile
stress (MPa)
Yield stress
(MPa)
R-value at
strain 15 (%)
291.1
291.4
279.8
279.8
285.8
284.9
128
125.8
120.9
121.7
123.7
124.1
0.69
0.72
1.08
1.1
0.79
0.88
RD1
RD2
DD1
DD2
TD1
TD2
68
69
70
71
72
73
Table 2
Lubricants and their details as provided by lube companies
Lubricant code
A
B
C
D
E
F
G
Lubricant type
Petroleum
oil
Draw
down bar
#0
Petroleum
oil
Draw
down bar
#0
Petroleum oil,
additive blend
Draw down
bar #0
Petroleum oil,
additive blend
Draw down
bar #0
Emulsified oil
(semisynthetic)
Draw down bar #0
Dry film
Mineral oil
based
Lube company
applies
Application method
Lubricant code
H
I
Lubricant type
Mineral oil
based
Draw
down bar
#0
Mineral oil
based
Draw
down bar
#0
Application method
J
K
L
Draw down bar #0
M
N
Water based
Water based
Water based
Dry film
Dry film
Draw down
bar #0
Draw down
bar #0
Draw down
bar #0
Lube company
applies
Lube company
applies
Fig. 2 3D measurements of surface texture (Al 5182-O, 1.5 mm): (a) EDT and (b) MF, provided by Honda Engineering
000000-2 / Vol. 00, MONTH 2015
Transactions of the ASME
105
106
107
108
Stage:
Page: 3
Total Pages: 9
Table 3 Measured roughness parameters in different areas on
the EDT and MF surfaces
Raa (lm)
Area 1
Area 2
Area 3
Area 4
Area 5
109
110
111
112
113
114
Rzb (lm)
EDT
MF
EDT
MF
1.719
1.414
1.111
1.463
1.197
1.574
1.282
1.121
1.485
1.238
16.991
14.546
12.022
14.3
13.505
14.03
11.145
11.135
12.96
10.5
The following evaluation criteria are used to determine the
“better” performance of the selected lubricants: (a) higher applicable BHF for the successfully drawn part and (b) shorter perimeter
in flange area (the perimeter is used in evaluation of the test
results because the formed flange is not exactly round and the
measurement of the perimeter avoids measuring and averaging
several draw-in lengths (Ld)).
2.4 Description of the Tooling and Test Procedure. The
CDTs were carried out in a 160 ton hydraulic press, which has a
maximum ram speed of 300 mm/s (12 in./s). The schematic of the
tooling is shown in Fig. 4. A draw die attached to the upper ram
a
Ra is the arithmetic average of the absolute values.
moves down and forms a cup sample with a stationary punch. The
b
Rz is average distance between the highest peak and lowest valley in each
preset constant BHF is provided by the CNC hydraulic cushion
sampling length.
pins. During the CDT, the punch force is measured by a load cell
and the die displacement is recorded by an infrared laser sensor.
The lubrication condition in this flange area influences the thickness The flange perimeter is measured using a flexible tape.
The cup draw test is selected because it is relatively simple to
distribution in the side wall of drawn cup. It also affects the draw-in
conduct and it communicates to the practical stamping engineer
length, Ld. As the blank holder pressure (Pb) increases, the frichow lubrication affects the metal flow and possible cup fracture.
tional stress (s) also increases based on Coulomb’s law (Eq. (1))
In this study, the draw ratio, the ratio of initial blank diameter to
cup diameter, was selected to be 2.0. In order to leave enough
s ¼ l Á Pb
(1)
flange area for measuring, the draw depth 80 mm was selected.
Round blanks with 304.8 mm diameter were cut from Al 5182-O
where s ¼ frictional shear stress, l ¼ coefficient of friction, and
sheet.
Pb ¼ blank holder pressure.
Fig. 3 Schematic of the cup drawing operation (CDT) and tooling
Fig. 4
Deep draw tooling used in CDT [7]
MONTH 2015, Vol. 00 / 000000-3
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
AQ1
Stage:
Page: 4
Total Pages: 9
Table 4 FE simulation parameters for obtaining BHF range for
CDT
Parameter
Description
Sheet material
Anisotropic values (average)
Flow stress curve
Yield criterion
Blank diameter
BHF
CoF
Punch stroke
Forming speed
Al 5182-O, 1.5 mm
R0 ¼ 0.71, R45 ¼ 1.09, R90 ¼ 0.84
VPB test data, as shown in Fig. 1
Yld 2000-2d
304.8 mm
16–24 ton
0.1, 0.11, 0.12
80 mm
40 mm/s
Table 5 Predicted results under various BHF and CoF
BHF
CoF
16
18
20
22
24
0.1
0.11
0.12
Formed
Formed
Formed
Formed
Formed
Fracture
Formed
Fracture
Fracture
Fracture
Fracture
Fracture
Fracture
Fracture
—
139
3
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
In order to obtain a workable range of BHF for the tests, the FE
analysis, using the commercial code PAM-STAMP, was carried out to
simulate the CDT process. The FE model was built in commercial
software PAM-STAMP. The sheet was modeled with four node quadrilateral shell elements, and the tools were assumed to be rigid.
The flow stress curve of Al 5182-O was considered to be independent of strain-rate in the deformation rate used in CDT. The
flow stress curve obtained from VPB test was used in the FE
model. The yield criterion Yld 2000-2d, having a better description of the anisotropic behavior of Al alloys, was used in the FE
model. The required eight yield parameters were characterized in
Numisheet 2005 Benchmark for Al 5182-O [15]. All the simulations were conducted under constant BHF and punch speed.
Table 4 summarizes the input parameters in the FE simulation.
In the FE simulations, the critical thinning (maximum thinning)
value of 20%, selected to predict the failure in forming of Al
5182-O is suggested by industrial experience from some of the
companies that form Al alloy sheets. The cup is formed, when the
Fig. 6 Flange perimeter recorded for 13 lubricant tests at 16
ton BHF (B, D, H, and N failed at 16 ton BHF). Note: The y-axis
on the graph does not start from 0. The error bands show the
deviation between samples.
FE Simulation of the CDT
Fig. 7 Flange perimeter recorded for five lubricant tests at 17
ton BHF (A, C, E, I, and J failed at 17 ton BHF). Note: The y-axis
on the graph does not start from 0. The error bands show the
deviation between samples.
Fig. 5 Test procedure for the evaluation of lubricants
000000-4 / Vol. 00, MONTH 2015
Stage:
Page: 5
Total Pages: 9
Fig. 8 Comparison between MF and EDT at (a) 16 ton BHF and (b) 17 ton BHF
Table 6 Flange perimeters prediction by FE simulations
BHF (ton)
16
17
CoF0.06 0.08 0.1 0.12 0.06 0.08 0.1 0.12
Flange perimeter (mm) 735 740 745 750 736 741 746 752
158
159
160
161
162
maximum thinning value is below 20%. Otherwise, the cup gets
fracture. As shown in Table 5, the drawability of 5182-O using
the present die set was predicted under different BHF and CoF. It
was determined that 16–18 ton is a reasonable range for evaluation of the performance of various lubricants in this study.
163
4
164
165
166
167
168
4.1 Test Results. Based on the FE simulation results listed in
Table 5, the CDTs were conducted under BHF 16 ton, 17 ton, and
18 ton, respectively; 17 ton was found to be the maximum useful
BHF for the experiments, since all the cups drawn with all lubricants cracked when BHF was 18 ton. The consistency of
Lubrication Tests, Analysis, and Results
lubrication condition is determined by using three samples for
each test. The test procedure for the evaluation of all lubricants is
shown in Fig. 5.
In the tests, the measurements of Ld could be easily affected by
the concentricity deviation of the sample position on the die.
Thus, the performance of the lubricants was evaluated by measuring the flange perimeter of the drawn cup using a tape. At 16
ton BHF, all lubricants listed in Table 2 were tested. Lubricants
that cracked at 16 ton (B, D, H, and N) were not considered for
next round of evaluation, using 17 ton BHF. As shown in Fig. 6,
lubricant F shows the minimum flange perimeter among all the
tested lubricants, indicating a better performance at 16 ton BHF.
At 17 ton BHF, cups could only form with five lubricants, including three wet lubricants G, K, L and two dry film lubricants F, M.
The results under 17 ton BHF are shown in Fig. 7. It can be concluded that, among all the wet lubricants, G, K, and L could be
determined as “better performing wet lubricants.” The dry film
lubricant F performed “best” at both 16 and 17 ton BHFs.
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
4.2 Effect of Surface Texturing. The friction behavior of Al
5182-O with EDT surface and MF surface are compared, as
187
188
Fig. 9 Comparison of flange perimeters obtained from simulation and experiment to predict
the CoF at 16 ton BHF for Al 5182O/MF
MONTH 2015, Vol. 00 / 000000-5
Stage:
Page: 6
Total Pages: 9
Fig. 10 Comparison of flange perimeters obtained from simulation and experiment to predict
the CoF at 17 ton BHF for Al 5182O/MF
Fig. 11 Thickness comparison between experiment and simulation of drawn cup with lubricant F: (a) rolling direction and (b) transverse direction
000000-6 / Vol. 00, MONTH 2015
Stage:
Page: 7
Total Pages: 9
Fig. 12 Thickness comparison between experiment and simulation drawn cup with lubricant I:
(a) rolling direction and (b) transverse direction
189
190
191
192
193
194
shown in Fig. 8. Lubricants K, J, and L were first tested at 16 ton
BHF. However, when BHF was increased from 16 ton to 17 ton,
the cups fractured when using lubricant J. As shown in Fig. 8, the
cups formed with EDT surface show smaller flange perimeters. It
can be concluded that, comparing to MF, EDT provides a better
lubrication condition in the current experimental procedure.
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
4.3 Prediction of CoF at Tool–Workpiece Interface. To
determine the CoF, the perimeter of the flange obtained at the end
of stroke in the simulation is compared to the results obtained in
the experiment using PAM-STAMP. The parameters used as input to
FE simulation are the same as parameters listed in Table 4, except
that (1) BHFs used in the simulation are 16 ton and 17 ton and (2)
the CoFs are 0.06, 0.08, 0.1, and 0.12. The predicted flange perimeters under different BHFs and CoFs are shown in Table 6.
As shown in Figs. 9 and 10, the flange perimeters obtained
from FE simulations and experiments are compared to determine
the CoFs for different lubricants under 16 ton BHF and 17 ton
BHF with MF blanks. It can be concluded that (i) the CoFs for
lubricants G and K are in the range of 0.08–0.1, (ii) the CoF for
lubricant F is around 0.08, and (iii) the CoF for the lubricant I is
around 0.12.
4.4 Comparison of Cup Thickness Variation Obtained
From Simulations and Experiments. In order to verify the simulation results (CoF), the thickness distributions in the drawn cup
obtained from experiments and simulations are compared. The
test results for lubricants F and I are selected to verify the results
of simulations. As mentioned in Sec. 4.3, the CoF of F is around
0.08 and the CoF of I is around 0.12. The cup samples drawn with
lubricants F and I were cut in rolling and transverse directions.
The thickness measurements along the rolling direction and transverse direction were completed using Starrett micrometer and are
shown in Figs. 11 and 12. It is seen that FE simulations provided a
good match with experimental results and the maximum error is
around 5%.
210
211
212
213
214
215
216
217
218
219
220
221
222
5
223
Summary and Conclusions
In this study, the methodology for evaluating the performance
of various commercial lubricants for forming aluminum alloy
sheets was established by using CDT and FE analysis. Two surface textures were investigated and compared with different lubricants. The principal conclusions from this study are summarized
as follows:
MONTH 2015, Vol. 00 / 000000-7
224
225
226
227
228
229
Stage:
Page: 8
Total Pages: 9
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
(1) CDTs were utilized to evaluate various wet and dry lubricants under different BHFs for Al 5182-O sheets with EDT
and MF surfaces. The effect of deformation on surface finish, as discussed in Ref. [16], was considered. The criteria
used in this study were able distinguish the performance of
selected lubricants.
(2) One of the dry film lubricants was found to perform better
than wet lubricants with the same amount of coating weight
(1 g/m2). In addition, EDT surfaces, with higher roughness,
could provide a better lubrication condition than MF surfaces for aluminum stamping.
(3) The FE model used in PAM-STAMP yields reasonable estimate
of CoFs and accurate thickness predictions when deep
drawing conditions prevail. The lowest CoF 0.08 was determined for one dry film lubricant under the current experimental condition.
Transactions of
246
Acknowledgment
247
248
249
250
251
252
253
254
The authors would like to extend special thanks to the member
companies of the Center of Precision Forming (CPF) that funded
this study. Special thanks are due to Honda North American Engineering center (Milan Jurich, Doug Staats), Honda R&D (Jim
Dykeman) and Honda Engineering (Dennis O’Connor) for supporting this project. The authors also thank to the lubricant companies
that provided samples and the Edison Welding Institute (Hyunok
Kim) for assisting in conducting the experimental part of this study.
References
255
256
257
[1] Groche, P., Nitzsche, G., and Elsen, A., 2008, “Adhesive Wear in Deep Drawing of Aluminum Sheets,” CIRP Ann. Manuf. Technol., 57(1), pp. 295–298.
[2] Meiler, M., Pfestorf, M., Merklein, M., and Geiger, M., 2004, “Tribological
Properties of Dry Film Lubricants in Aluminum Sheet Metal Forming,” 2nd
ICTMP, Nyborg, Denmark, June 15–18, pp. 489–500.
000000-8 / Vol. 00, MONTH 2015
[3] Meiler, M., and Jaschke, H., 2005, “Lubrication of Aluminum Sheet Metal
Within the Automotive Industry,” Adv. Mater. Res., 6-8, pp. 551–558.
[4] Wei, J., Erdemir, A., and Fenske, G. R., 2000, “Dry Lubricant Films for Aluminum Forming,” Tribol. Trans., 43(3), pp. 535–541.
[5] Meiler, M., Pfestorf, M., Geiger, M., and Merklein, M., 2003, “The Use of Dry
Film Lubricants in Aluminum Sheet Metal Forming,” Wear, 255(7), pp.
1455–1462.
[6] Kim, H., Sung, J., Goodwin, F. E., and Altan, T., 2008, “Investigation of Galling in Forming Galvanized Advanced High Strength Steels (AHSSs) Using the
Twist Compression Test (TCT),” ASME J. Mater. Process. Technol., 205(1),
pp. 459–468.
[7] Kim, H., Sung, H., Sivakumar, R., and Altan, T., 2007, “Evaluation of Stamping Lubricants Using the Deep Drawing Test,” Int. J. Mach. Tools Manuf.,
47(14), pp. 2120–2132.
[8] Subramonian, S., Kardes, N., Demiralp, Y., Jurich, M., and Altan, T., 2011,
“Evaluation of Stamping Lubricants in Forming Galvannealed Steels for Industrial Application,” Int. J. Mach. Tools Manuf., 133(6), p. 061016.
[9] Liewald, M., Wagner, S., and Becker, D., 2010, “Influence of Surface Topography on the Tribological Behaviour of Aluminium Alloy 5182 With EDT
Surface,” Tribol. Lett., 39(2), pp. 135–142.
[10] Hartfield-Wunsch, S., Cohen, D., Sanchez, L., and Brattstrom, L., 2011, “The
Effect of Surface Finish on Aluminum Sheet Friction Behavior,” SAE Technical Paper No. 2011-01-0534.
[11] Raharijaona, F., Roizard, X., and Stebut, J. V., 1999, “Usage of 3D Roughness
Parameters Adapted to the Experimental Simulation of Sheet–Tool Contact
During a Drawing Operation,” Tribol. Int. 32(1), pp. 59–67.
[12] Zhou, R., Cao, J., Wang, Q. J., Meng, F., Zimowski, K., and Xia, Z. C., 2011,
“Effect of EDT Surface Texturing on Tribological Behavior of Aluminum
Sheet,” J. Mater. Process. Technol., 211(10), pp. 1643–1649.
[13] Groche, P., and M€ller, N., 2012, “Tribological Investigation of Deep-Drawingo
Processes Using Servo Presses,” ASME 2012 International Manufacturing Science and Engineering Conference, Proceedings of the International Conference
on Tribology Materials and Processing, pp. 127–137.
[14] Nasser, A., Yadav, A., Pathak, P., and Altan, T., 2010, “Determination of
the Flow Stress of Five AHSS Sheet Materials (DP 600, DP 780, DP 780-CR,
DP 780-HY and TRIP 780) Using the Uniaxial Tensile and the Biaxial Viscous Pressure Bulge (VPB) Tests,” J. Mater. Process. Technol., 210(3), pp.
429–436.
[15] Brem, J. C., Barlat, F., Dick, R. E., and Yoon, J. W., 2005, “Characterizations
of Aluminum Alloy Sheet Materials Numisheet 2005,” Numisheet 2005 Part B,
pp. 1179–1190.
[16] Leu, D. K., and Sheen, S. H., 2013, “Roughening of Free Surface During Sheet
Metal Forming,” ASME J. Manuf. Sci. Eng., 135(2), p. 024502.

Evaluation of Lubricants for Stamping of Al 5182

Transcription

Similar documents

BDE75 P34HR.indd - Klüber Lubrication

Competence in Lubricants Has a Name

jlm phoenix australia

TECNOLOGIE E PRODOTTI CHIMICI PER LA LAMINAZIONE A

Flyer-COF 8thSept Reded...2013

Lubricants and Related Items

Certificate of Registration

Forming Lubricants - Fuchs Lubricants Benelux

CP ScrewGuard ROTAIR.indd

Megasol•KAT EN 1106