The effect of molecular structure of six-element N-containing heterocyclic compounds on their wear properties

The friction and wear properties of N-containing heterocyclic compounds (pyridine, pyrimidine, pyrazine, pyridazine and triazine) which have the same cyclic structure except for the number and position of N atoms were evaluated by a four-ball machine and a SRV machine. X-ray photoelectron spectroscopy was used to examine the binding energy of N_1s on the rubbed surface. The results indicate that the effect of these compounds on antiwear properties is improved with the increase of N atom number and N elements exist in the boundary lubricating film mainly as organic amine (RNH₂) and nitrites. The mechanism discussed in this paper is connected with different bond length and resonance energy of these compounds.