Abstract
In recent years, various workers have attempted to improve the lubricating properties of solid lubricants, particularly at high temperatures, by mixing them with inorganic salts. Since graphite forms interlamellar compounds with a variety of inorganic salts, this presents a convenient means of producing evenly dispersed and reproducible combinations. Graphite reacts with ferric chloride vapour to form such a compound in which ferric chloride planes alternate with the carbon planes in the graphite lattice. Although formed from a hygroscopic salt, the compound is quite stable under normal conditions.
The frictional characteristics of this material have been assessed over a range of temperatures using a pin-and-disc-type friction rig. The results have been compared with those obtained using the parent graphite and molybdenum disulphide as reference lubricants.
It is concluded that the intercalation of an inorganic salt in the graphite structure can lead to certain improvements in lubricating properties, particularly with respect to the adhesion of lubricant to substrate in dry applications; salts other than ferric chloride may be more suitable for this purpose.
Get full access to this article
View all access options for this article.