Hello every body,
I,m engineer and I,m doing an study about the presence of metalic elements in used oils.
I want to know the metallurgy reasons of apareance of this elements in oil:
Al: why is used in pistons? and in cylinder heat
Cu: why is used in coolings parts?
Si:why is used in engine?
Fe:why it can be appear in oil?
Cr: why is used in bearing?
Pb: why can be appear apart of procedence of fuel?
Thanks for your help

These are wear metals only except silicon.silicon is an abrasive and is coming from dirt and dust.All the other metals are a part of the engine metallurgy(metal alloy) and depends on the type of OEM,(CUMMINS,CAT,etc...).

Silicon can be from anti form agents also.Copper also can come from coolant ingress.

Judging from the question you don't know anything about internal combustion engines. I might suggest you do a little research on engines first so you can understand what the parts are in a engine, what they are made of and what their function is. After you have a basic understanding of the internals of a engine it might be easier to answer questions for you as to specifics of different wear metal combinations found in used oils analysis's.