Abstract

In this study, porous materials were applied to the surface materials of electrical sliding contacts to produce long and stable operations. The proposed sliding contacts consist of a rotating circular grooved porous disk and a stationary rider having a spherical surface. We conducted the experimental analysis from two perspectives. The first perspective was to inspect the effect of the design parameters on the electrical conductivity and the frictional characteristics; this was done by performing tests under various loads applied on the sliding contacts. The second perspective was to investigate the durability and stability of the sliding contacts by using the tests for a long operating time under a constant applied load. Our experimental results proved that the porous disk generated a lower and a more stable contact voltage and frictional force than the conventional nonporous solid disk. This effect is significant when a large curvature radius of grooves is provided on the disk surface. These results are attributable to the reduction of the hydrodynamic fluid force by the porous material and the grooves; the porous material yields lower hydrodynamic pressure due to the seepage of the lubricant oil across the interface between the oil film and the porous matrix and the grooves enhance the reduction of the hydrodynamic effect because of oil leakage to the downstream region. These factors reduce the oil film thickness between the disk and rider and facilitate the metal contact, and thereby a porous grooved disk generates higher electrical conductivity than a conventional solid disk.

References

1.
Wang
,
P.
,
Yue
,
W.
,
Lu
,
Z.
,
Zhang
,
G.
, and
Zhu
,
L.
,
2018
, “
Friction and Wear Properties of MoS2-Based Coatings Sliding Against Cu and Al Under Electric Current
,”
Tribol. Int.
,
127
, pp.
379
388
. 10.1016/j.triboint.2018.06.028
2.
Kalin
,
M.
, and
Poljanec
,
D.
,
2018
, “
Influence of the Contact Parameters and Several Graphite Materials on the Tribological Behaviour of Graphite/Copper Two-Disc Electrical Contacts
,”
Tribol. Int.
,
126
, pp.
192
205
. 10.1016/j.triboint.2018.05.024
3.
Grandin
,
M.
, and
Wiklund
,
U.
,
2018
, “
Influence of Mechanical and Electrical Load on a Copper/Copper-Graphite Sliding Electrical Contact
,”
Tribol. Int.
,
121
, pp.
1
9
. 10.1016/j.triboint.2018.01.004
4.
Grandin
,
M.
, and
Wiklund
,
U.
,
2018
, “
Wear Phenomena and Tribofilm Formation of Copper/Copper-Graphite Sliding Electrical Contact Materials
,”
Wear
,
398–399
, pp.
227
235
. 10.1016/j.wear.2017.12.012
5.
Deng
,
C.
,
Yin
,
J.
,
Zhang
,
H.
,
Xiong
,
X.
,
Wang
,
P.
, and
Sun
,
M.
,
2017
, “
The Tribological Properties of Cf/Cu/C Composites Under Applied Electric Current
,”
Tribol. Int.
,
116
, pp.
84
94
. 10.1016/j.triboint.2017.07.005
6.
Zhang
,
Y. Y.
,
Zhang
,
Y. Z.
,
Du
,
S. M.
,
Yang
,
Z. H.
, and
Shangguan
,
B.
,
2018
, “
Tribological Properties of Pure Carbon Strip Affected by Dynamic Contact Force During Current-Carrying Sliding
,”
Tribol. Int.
,
123
, pp.
256
265
. 10.1016/j.triboint.2017.12.032
7.
Huang
,
W.
,
Kong
,
L.
, and
Wang
,
X.
,
2017
, “
Electrical Sliding Friction Lubricated With Ionic Liquids
,”
Tribol. Lett.
,
65
(
1
), p.
Article 17
. 10.1007/s11249-016-0802-8
8.
Chen
,
J.
,
Xia
,
Y.
,
Hu
,
Y.
, and
Hou
,
B.
,
2017
, “
Tribological Performance and Conductive Capacity of Ag Coating Under Boundary Lubrication
,”
Tribol. Int.
,
110
, pp.
161
172
. 10.1016/j.triboint.2017.02.006
9.
Kaneko
,
S.
, and
Taura
,
H.
,
2012
, “
Tribological Characteristics of Electrical Sliding Contacts With Oil Impregnated Porous Materials: Effects of Permeability of Porous Disk on Frictional Characteristics and Electric Conductivity
,”
Trans. Jpn. Soc. Mech. Eng. Ser. C
,
78
(
791
), pp.
2613
2623
. 10.1299/kikaic.78.2613
10.
Kaneko
,
S.
,
Taura
,
H.
,
Fukasawa
,
R.
, and
Kanai
,
H.
,
2016
, “
Lubrication Characteristics of Electric Sliding Contacts Consisting of Rotating Circular Grooved Disk and Stationary Rider With Spherical Surface Under Lubricated Condition
,”
ASME J. Tribol.
,
138
(
1
), p.
011705
. 10.1115/1.4031393
11.
Beavers
,
G. S.
,
Sparrow
,
E. M.
, and
Magnuson
,
R. A.
,
1970
, “
Experiments on Coupled Parallel Flows in a Channel and Bounding Porous Medium
,”
Trans. ASME J. Basic Eng.
,
92
(
4
), pp.
843
848
. 10.1115/1.3425155
12.
Goldstein
,
M. E.
, and
Braun
,
W. H.
,
1971
, “
Effect of Velocity Slip at a Porous Boundary on the Performance of an Incompressible Porous Bearing
,” NASA Technical Note TN D-6181.
13.
Kaneko
,
S.
, and
Hashimoto
,
Y.
,
1995
, “
A Study on the Mechanism of Lubrication in Porous Journal Bearings: Effects of Dimensionless Oil-Feed Pressure on Frictional Characteristics
,”
Trans. ASME J. Tribol.
,
117
(
2
), pp.
291
296
. 10.1115/1.2831245
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