Research Progress on Evaluation Methods of Tribological Properties of Lubricants

The requirements in lubricity evaluation of lubricants were summarized, the application of four-ball tester method, ball-plate tester method, loop-block tester method and V-block tester method in the tribological property evaluation tests of lubricating fluid and lubricating grease was introduced, and the advantages and disadvantages of these four methods were analyzed. The limitations and improvements of the evaluation methods were also discussed:four-ball tester method was the most widely applied method; ball-plate tester method was only suitable for lubricating grease; loop-block tester method and V-block tester method were usually used in extreme-pressure property evaluation. Additionally, further exploration of friction and wear formation process and lubrication mechanism would be accomplished by combining tribological methods with instrumental analysis methods.