What is the green stuff on the outside of copper gutters and is it good for corrosion prevention?
That green stuff on the outside of copper is what we call patina. It is not a tightly adhering oxide film such as the film on aluminum, but rather an electrically resistant coating. The patina slows corrosion because it resists the electron flow in a corrosion cell. • Where do composite materials come from? A composite material is a combination of two or more materials that show better properties than either of the individual components. Polyester resin plus styrene monomer with an organic peroxide added, forms a thermo-set or composite material. • Is the corrosion by-product (white rust) of zinc a good protective finish? White rust is a loose powdery coating which is not a good protective finish for corrosion protection. Zinc is used as a barrier and an anode in the cathodic protection process. Unprepared zinc is an inhibitor to a good bond. • If corrosion cost to the US is $600,000,000, where is the most corrosion found? Close to 35% of the total cost of corrosion is located in the u
