Galling is a severe type of wear usually occurring at high normal stress and small relative movement between contacting surfaces. Surface protrusions, plastic deformation, magnified increases in roughness, and final seizure of the coupled pair characterize galling. Austenitic stainless steels are particularly prone to this surface disruption and a number of processes have been used to reduce or eliminate this extreme form of adhesion. In this study 316 stainless steel surfaces are treated by means of the microwelding process electrospark alloying (ESA). A variety of electrode compositions ranging from very hard (WC) to very soft (Ag) were used in both self mated and single surfaced tests. A standard gall test supplemented by a recording torque wrench was used for evaluation of surfaces. Tests were run at normal stresses of 35.1, 123, and 211 MPa. While all the compositions evaluated eliminated galling some showed abrasive cutting and the rotational torque requirements were high. Cobalt used in a self mated couple and silver used in a single surfaced couple were found to be the superior electrode materials for eliminating galling tendencies of 316 stainless steel.

Issue Section:
Research Papers
Topics:
Galling, Stainless steel, Electrodes, Stress, Adhesion, Cobalt, Cutting, Deformation, Silver, Surface roughness, Torque, Torque wrenches, Wear
1.
“Standard Test Method for Galling Resistance of Materials,” ASTM G98-89, Philadelphia: ASTM, 1989.
2.
Ives, L. K., Petersen, M. B., and Whitenton, E. P., “The Mechanism, Measurement, and Influence of Properties on the Galling of Metals,” NIST Publication 89-4064, ORNL/Sub/83-21322/01, Dec. 1989.
3.
Budinski
K. G.
, “
Incipient Galling of Metals
,”
Wear
, Vol.
74
,
1981–1982
, pp.
93
–
105
.
4.
Schumacher, W., “The Galling Resistance of Silver, Tin, and Chrome Plated Stainless Steels,” Wear of Materials, ASME New York, NY, pp. 186–196.
5.
Sheldon, G. L., and Johnson, R. N., “Electro-Spark Deposition—A Technique for Producing Wear Resistant Coatings,” Wear of Materials, ASME New York, NY, 1985, pp. 388–396.
6.
Johnson
R. N.
, and
Sheldon
G. L.
, “
Advances in the Electro-Spark Deposition Coating Process
,”
Journal of Vacuum Science and Technology
, Vol.
4
,
1985
, pp.
2740
–
2746
.
7.
Verkhoturov
A. D.
, and
Podchernyaeva
I. A.
, “
Physicochemical Basis of Creating Electrode Materials for Electrospark Alloying
,”
Elektronnaya Obrabotka Materiolov
, Vol.
5
,
1987
, pp.
17
–
20
.
8.
Brown
E. A.
,
Sheldon
G. L.
, and
Bayoumi
A. E.
, “
A Parametric Study on Improving Tool Life by Electrospark Deposition
,”
Wear
, Vol.
138
,
1990
, pp.
137
–
151
.
9.
Topinka, W. A., and Sheldon, G. L., “High Stress Wear Behavior of Ti-6Al-4V with Surface Modification by Electrospark Alloying,” SAE SP 795, Worldwide Progress on Adiabatic Engines, 1989, pp. 65–70.
10.
Hoft, H., Bottcher, D., and Steinelk, R., Ziss-Mitteilungen, Vol. 10, 1968, pp. 146–152.
11.
Galinov
I. V.
, “
Investigation of the Composition of Ag, Ni, and Ag-Ni Pseudo-Alloy Coatings Applied by Electro-spark Alloying on a Cu Substrate
,”
Surface and Coating Technology
, Vol.
56
,
1993
, pp.
131
–
135
.
12.
Johnson, R. N., “Low Friction and Galling Resistant Coatings and Processes For Coating,” United States Patent 4,649,086, Mar. 10, 1987.
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