polished surfaces VS non-polished surfaces

[shirr_mozz]

first i wrote my question other place , but someone told me to make a new post , so i do !!

as the matter of fact im a student and i only have a question :

why it takes more loger to a polished surfaces to be corroded but after start it continues in very high rate even more than a nonpolished surface. but in nonpolished surfaces it takes a shorter time to start but a longer time when it continues!!
Why it is like this ?

thanx experts

 

[Seastar]

Umm.... the polish process reduces the available area for contact and thus corrosion to start, I cannt recall the exact science but a rough surface has alot more area plus stress points for corrosion to work and thrive and perhaps "retain" electrolitic compounds. Best to polish and banish these beasties!!
As another thought; all corrosion prevention appears to involve a reduction in available surface area!!!!! be it wax , paint polish or plate. Interesting!!!

 

[shirr_mozz]

so where can i find the exact answer , any specific forum or web site ???