An investigation was conducted to determine the effects of the vapor deposition process and. the interstitial coating thickness on the overall joint conductance of metallic interfaces. Eight aluminum 6061-T6 test specimens were coated with indium and tested while in contact with uncoated aluminum 6061-T6 specimens. In the first test set, all specimens were coated to a thickness of 3.51 μm, but the vapor deposition process was varied to produce both single and multiple-layered coated specimens. In the second test set, the coating thickness was varied from 0.026 μm to 3.51 μm. The results indicated that when creating multiple layered coatings, oxidation and thermal cycling caused poor layer adhesion, and resulted in significantly reduced dimensionless contact conductance enhancement factors than for single-layered coatings with an equivalent thickness. Additionally, the results demonstrated that the thermal contact conductance could be enhanced to much greater levels than previously reported in the literature, and that the dimensionless enhancement factor asymptotically approached a maximum enhancement value. A theoretical maximum enhancement limit has been presented for comparison with the experimental data.

Issue Section:
Contact Conductance
Keywords:
Augmentation and Enhancement, Conduction
Topics:
Coatings, Contact resistance, Vapor deposition, Aluminum, Electrical conductance, Adhesion, Heat conduction, Oxidation
1.
Al-Astrabadi, F. R, Snaith, B., Probert, S. D., and O’Callaghan, P. W., 1981, “Prediction of Optimum Interfacial Filler Thickness for Minimum Thermal Contact Resistance,” AIAA Paper No. 81–1166.
2.
American Society of Metals, 1989, Metals Handbook: Corrosion, Vol. 13, 9th ed., pp. 750–752, 770–778.
3.
Antonetti
V. W.
, and
Yovanovich
M. M.
,
1985
, “
Enhancement of Thermal Contact Conductance, by Metallic Coatings: Theory and Experiment
,”
ASME JOURNAL OF HEAT TRANSFER
, Vol.
107
, pp.
513
–
519
.
4.
Chung, K. C, Sheffield, J. W., and Sauer, H. J., Jr., 1990, “Effects of Metallic Coated Surfaces on Thermal Contact Conductance: An Experimental Study,” Proc. 6th Miami International Symposium on Heat and Mass Transfer, Miami Beach, FL, Dec. 10–12.
5.
Fletcher
L. S.
,
1988
, “
Recent Developments in Contact Conductance Heat Transfer
,”
ASME JOURNAL OF HEAT TRANSFER
, Vol.
110
, pp.
1059
–
1070
.
6.
Fletcher, L. S., and Peterson, G. P., 1986, “The Effect of Interstitial Materials on the Thermal Contact Conductance of Metallic Junctions,” Proceedings of the Heat Transfer in Thermal Systems Seminar—Phase II, National Cheng Kung University, Tainan, Taiwan, Jan. 13-14, pp. 1–8.
7.
Fried, E., and Kelly, M. J., 1965, “Thermal Conductance of Metallic Contacts in a Vacuum,” in: Proc. AIAA Thermophysics Specialist Conference, Monterey, CA, Sept. 13-15, AIAA Paper No. 65–661.
8.
Kang, T. K., 1989, “Effect of Metallic Coatings on the Thermal Contact Conductance of Turned Surfaces,” M.S. Thesis, Department of Mechanical Engineering, Texas A&M University, College Station, TX.
9.
Kang
T. K.
,
Peterson
G. P.
, and
Fletcher
L. S.
,
1990
, “
Enhancing Thermal Contact Conductance Through the Use of Thin Metallic Coatings
,”
ASME JOURNAL OF HEAT TRANSFER
, Vol.
112
, pp.
864
–
871
.
10.
Madhusudana
C. V.
, and
Fletcher
L. S.
,
1986
, “
Contact Heat Transfer—The Last Decade
,”
AIAA Journal
, Vol.
24
, No.
3
, pp.
510
–
523
.
11.
Majumdar
A.
, and
Tien
C. L.
,
1991
, “
Fractal Network Model for Contact Conductance
,”
ASME JOURNAL OF HEAT TRANSFER
, Vol.
113
, pp.
516
–
525
.
12.
Mal’kov
V. A.
, and
Dobashin
P. A.
,
1969
, “
The Effect of Soft-Metal Coatings and Linings on Contact Thermal Resistance
,”
Inzhenemo-Fizicheshii Zhurnal
, Vol.
17
, No.
5
, pp.
871
–
879
.
13.
Ochterbeck
J. M.
,
Peterson
G. P.
, and
Fletcher
L. S.
,
1992
, “
Thermal Contact Conductance of Metallic Coated BiCaSrCuO Superconductor/Copper Interfaces at Cryogenic Temperatures
,”
ASME JOURNAL OF HEAT TRANSFER
, Vol.
114
, pp.
21
–
29
.
14.
Snaith, B., O’Callaghan, P. W., and Probert, S. D., 1984, “Use of Interstitial Materials for Thermal Contact Conductance Control,” AIAA Paper No. 84–0145.
15.
Tsao, Y. H., and Heimburg, R. W., 1970, “Effects of Surface Films on Thermal Contact Conductance: Part 2-Macroscopic Experiments,” ASME Paper No. 70-HT/SpT-27.
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