Cob heatsinks changing colors... Is this normal?

[ganjafather27]

Hey so I'm taking apart my 1 year old cob build to re frame it and I've noticed that the Heatsinks are bleaching or something... It's closest to the chips and it's sort of yellowish.

Is this normal? If not, what's going on?

 

[PSUAGRO.]

Yes normal, oxidation....... faster with heat.

 

[ganjafather27]

Yes normal, oxidation....... faster with heat.

Thanks man