Study on Antiwear Properties of Compounds Containing Molybdenum in Lubricating Grease

A four-ball machine was used to evaluate the antiwear performances of five kinds of compounds containing molybdenum in lubricating grease.These compounds include molybdenum dialkyldithiophosphate(MoDDP),molybdenum dialkyldithiocarbamate(MoDTC),sulphur and phosphorus free organo-molybdenum,molybdenum trioxide and ammonium molybdate.The results indicated that all of the three organo-molybdenum compounds have excellent antiwear properties in lubricating grease,especially the high concentration of MoDDP under high load and the sulphur and phosphorus free organo-molybdenum compound under low load.The two solid particles containing molybdenum also have good antiwear properties in greases,particularly ammonium molybdate,which makes it possible to introduce molybdenum into grease by adding inorganic solid particles directly.