Abstract:

In this paper，the crankcase simulation test was carried out to investigate the antioxidation of MoDTC additive,and the oxidized oil and deposits on aluminum board were seperately characterized by FTIR and EDS. Tribological properties of unoxidized and oxidized oils were examined using four-ball machine,and SEM、EDS were employed to analyze micromor-phologies and element constitute of worn surfaces.Results show that: (1)MoDTC has good antioxidation under moderate and low temperature,which could increase the stability of oil;in high temperature,the antioxidation property of oil with MoDTC additive went down firstly, then up with increasing additive content.（2）The mass of depositsincreased firstly, and then decreased with the increase of additive content.Elemental analysis of deposits revealed that the decomposition products were significant comstituent parts of deposits.(3)Under test conditions,the friction-reducing and extreme-pressure properties were weakened by oxidation, while the antiwear property was strengthened.

Key words: MoDTC, crankcase simulation test, antioxidation, tribological properties