Research On Tribological Properties Of Fluorine-containing Lubricant And Composition Analysis

Polytetrafluoroethylene(PTFE) has excellent lubrication properties because of its structural characteristics, it's one of important solid lubricant materials. It will improve the properties of anti-wear and friction reduction of lubricant oil, and improve the working life of the equipments, decreasing energy consumption, if put PTFE into the lubricant oil.This paper aims to study new type PTFE lubricating oil, PTFE lubricating paste and PTFE lubricating grease developed by Russia. Tribological property of the three lubricants were researched, including properties of anti-wear, friction reduction, friction changed with rotational speed, friction changed with temperature and Tribological property on thrust cycles friction pair, pin-disc friction pair and ball-disc friction pair. Fourier transform infrared spectroscopy was used to analyze the functional group and the change of the three lubricants. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) were used to analyze the tribofilm of the three lubricants.Experimental results show that the friction reduction of the three lubricants on high load are better than them on low load, and PTFE lubricating oil is the best one of the three. Test the average wear scar of the three lubricants on different loads, the results show that the diameter of wear scar of three lubricants have large increasing value as loads increase from 196N to 390N, then the increasing value slow down, the diameter of wear scar of PTFE lubricating grease is the lowest of the three, so PTFE lubricating grease has the best properties of anti-wear of the three. The friction of PTFE lubricating oil and PTFE lubricating grease both decreased when load increasing, the friction of PTFE lubricating paste decreased when rotational speed increasing firstly, and then increase. When the temperature of the three lubricants between 20℃and 80℃, the friction reduction properties of the three lubricants stable, the friction increased 10% when the temperature of the three lubricants higher than 80℃; PTFE lubricating oil and PTFE lubricating paste have good and stable property of friction reduction on the three friction pair, PTFE lubricating grease have good and stable property of friction reduction on thrust cycles friction pair, is difficult to form a stable lubricating film on pin-disc friction pair and ball-disc friction pair.By studying the three lubricants' functional group before and after the experiment, using flourier transform infrared spectroscopy(FTIR),show that there are aroma -CH₃ or Through analysis and comparison by using scanning electron microscopy(SEM) and energy dispersive X-ray spectroscopy(EDS),the lubricant molecules adsorbed on the friction surface, formed high-intensity absorption film when the lubrication in lower load; the generation of chemical reaction between lubricant additives and friction surface material, form chemical migration film, the properties of anti-wear and friction reduction of this kind of film are better than absorption film formed in lower load.