A Study in the EP Activity Evaluation of certain 1,2,4-Triazoles in the Four Ball Test

Department of Applied Chemistry, Institute of Technology, Banaras Hindu University, Varanasi-221 005

Manuscript received 1 April 1991, revised 30 December 1991, accepted 6 March 1992

The potential extreme pressure activity of certain 3-mercapto-4-aryl-5-(4'-pyridyl)-1,2,4-triazoles in paraffin oil has been evaluated with reference to a commercial S-P containing additive on a four-ball machine. 3-Mercapto-4-p-chlorophenyl-5-(4'cpyridyl)-1,2,4-triazole showing lower values of wear-scar diameter (0.60 mm) and friction coefficient (0.018) at ISL (80 kgf) and higher values of 2.5 second SDL, (90 kgf), weld load (224 kgf), mean Hertz load (41 kgf) and flash temperature parameter (244), was found to be best. This was corroborated and confirmed by the study of the surface topography and surface chemistry of wear-scar matrix by scanning electron microscopy and Auger electron spectroscopy techniques respectively.