Pipe, aluminum graphite

E6.2. Predict whether or not galvanic corrosion will cause the following alloys to be subjected to leaching (i) carbon and carbon steel alloys in an oxidizing atmosphere, (ii) steel rivets in aluminum drain gutters, (iii) copper-nickel alloy in refinery condenser tubes, (iii) graphite fiber-reinforced aluminum composites, (iv) brass in water, (v) iron-chromium alloys, and (vi) carbon steel pipe in contact with the weld to stainless steel pipe. 

A Figure 2.17 Some familiar examples of metals and nonmetals. The non metals (from bottom left) are sulfur (yellow powder), iodine (dark, shiny crystals), bromine (reddish brown liquid and vapor in glass vial), and three samples of carbon (black charcoal powder, diamonds, and graphite in the pencil lead). The metals are in the form of an aluminum wrench, copper pipe, lead shot, silver coins, and gold nuggets. 

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