Frictional Behavior of Soft Bi2S3 Coatings: Experimental Results and DFT Modeling

GERMAN PRIETO; C. MULLER; BRUNO PILOTTI; M. DENNEHY; A. JUAN; R. FACCIO; E. BROITMAN; W. TUCKART

Chicago, Illinois

Congreso; STLE Tribology Frontiers Conference; 2019

Society of Tribologysts and Lubrication Engineers

In harsh environments, solid lubricants are often the best choice inorder to reduce friction and wear, thanks to their resistance to hightemperatures and contact pressures. For this purpose, traditional solid lubricants, such as graphite and molybdenum disulfide (MoS2) have been extensively used. However, all of them show weaknesses in some aspects. For example, graphite needs moist air, while MoS2 requires high contact pressures in order to properly lubricate [1].Bismuth trisulfide (Bi2S3) is a promising solid lubricant candidate that has not been extensively studied to date [2].The aim of this study was to analyze the frictional behavior of a Bi2S3 based soft coating under variable relative humidity (RH) atmospheres and contact pressures. In addition, its performance was compared to a MoS2 coating produced by the same method. The interactions between the Bi2S3 coating and the steel substrate were modelled using Density Functional Theory models.