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Frictional coefficients are perhaps more dependent on surface rather than material properties.
Surface finish, cleanliness and lubrication of the mating surfaces largely determine the actual frictional resistance between mating surfaces.
A figure of 0.58 for unlubricated, self-mating, clean steel surfaces has been quoted and this may be taken as a guide for most stainless steels (austenitics, ferritics and duplex).
The martensitic types, when hardened, may have lower frictional coefficients, nearer to the 0.2 values quoted for lubricated, hardened steel self-mating surfaces.
The corrosion resistance of stainless steels means that the surface characteristics, including frictional properties, are unlikely to be affected in service due to corrosion issues, provided the correct grade has been selected.
The softer, high ductility austenitic types, such as 304 and 316, can suffer from galling and, in extreme cases, seizure (cold welding). The frictional properties under these conditions can be significantly affected.
Surface finish (including tolerances) and lubrication play an important role in preventing galling and seizure.