You are reading a single comment by @ugosantalucia and its replies.
Click here to read the full conversation.
-
Metal wearing off surfaces presumably
-
it is not just the dirt from the road
ftfy. Foreign material contamination is definitely a thing, but in a clean room the wear particles are the culprit. I think the blackness of it is due to mixing aluminium oxide with transition metals, mostly iron but also Ni Cr V Mo Mn etc. which are present as alloying elements in the steel parts.
hippy
gbj_tester
@ugosantalucia
interestingly, even chains on turbo bikes get black, suggesting it is not the dirt from the road…