Structure of the boundary layer on sintered materials sliding in chemically active media

Abstract

1. It has been established that the antiscuffing action of sulfur-containing additions in iron-base materials involves their decomposition and the propagation of chemical reactions with the participation of certain elements from the surrounding medium. The compounds responsible for the formation of antiscuffing layers are FeS, FeSO4, and δ-FeO(OH). 2. It is shown that the lubricating effect of chloride compounds added to liquid lubricants or sintered iron-base materials may be due to the formation of iron chlorides on rubbing surfaces during friction and to the subsequent hydrolysis of these chlorides, with the appearance in the contact zone of a solid lubricant, namely, hexagonal iron monohydroxide. 3. The difference in lubricating action between layers chemically modified by sulfur and chlorine is apparently due to the differences in capacity for hydrolysis between FeSO4 and FeCl2 and in load carrying capacity between the sulfide and chloride layers on which hydrolysis takes place.