Molybdenum tetrasulphide

Molybdenum Tetrasulphide, MoS, is formed by decomposition of a perthioniolybdate with a dilute acid. ... 

Lead oxide in conjunction with antimony trioxide showed a synergistic improvement in performance , as shown in Table 7.2. Bartz showed a marked improvement in wear life for a three-component mixture of molybdenum disulphide, graphite and antimony tetrasulphide. Like those of Centers , his tests were carried out with unburnished/non-run-in films, against an uncoated block, and may not be representative of practical engineering situations. 

Lavik et al ° reported up to 400% improvement in wear life, and lower friction at high or low temperature, when antimony trioxide was used in polyimide or polybenzothiazole-bonded films. Lower improvements, up to 270%, were obtained with antimony trisulphide, while Bartz reported that the addition of both graphite and antimony tetrasulphide (or antimony thio-antimonate Sb(SbS4)) gave a much greater improvement in the life of a polybutyltitanate-bonded molybdenum disulphide film than either of the additives separately. 

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