Highly Chlorinated Methanes and Ethanes on Ferrous Surfaces
Peter V. Kotvis, L. Huezo, William S. Millman, W.T. Tysoe · ACS symposium series · 1992
Chlorinated hydrocarbons are an important class of extreme pressure (EP) additives to metalworking fluids for preventing seizure between the contacting metal surfaces. It is proposed that they function by thermally decomposing at the interface between these surfaces, forming an iron halide + carbon anti-seizure film. This film is continually removed by the frictional forces acting at the surface and the net film thickness is the result of a dynamic balance between growth and removal. The film growth and removal rates are measured independently, and the film thickness is calculated from these data as a function of applied load. The experimental data for seizure load versus additive concentration is well reproduced by assuming that seizure occurs when the thickness of this protective film diminishes to zero.