A study on the prediction of seizure behavior of steels with molecular film lubrication at low temperature in a vacuum

In older to investigate the seizure mechanism of sliding components, a seri es of friction tests were carried out by sliding a steel ball against a car bon steel plate lubricated with a LB molecular film in a vacuum of 10(-4) t o 10(-2)Pa at the temperatures from 20K to 300K. The Vickers hardness of ma terials at 20K was also measured. The results indicate that initial times o f seizure are strongly correlated with the low temperature hardness of the materials. There exists a critical value of initial temperature T-c for cer tain mating materials, below which the materials will not seize. The critic al temperature is determined by the mechanical properties of the metals and not by surface lubrication. An empirical qualitative expression is introdu ced to give the relationship between the initial time of seizure and fricti on conditions, material properties and surface lubrication, The average tem perature of friction sur face was estimated by calculation. The calculated results show that the critical temperature for friction surface is near the melting point of mating materials.