Galvanized steel advantages

Cost comparisons have also been made between galvanized steel and other construction materials. A survey by Steven Winter Associates (1980) showed that it was up to 19% cheaper to use galvanized steel framing instead of wood for house units (depending on location) in a year in which wood was cheap—its cost fluctuates far more than that of galvanized steel. British Steel Corporation in 1973 showed the advantage of galvanized steel compared with aluminum for ISO-type containers. 

The electrical conductivity of ethanol is higher than hydroprocessed, conventional fuels. This theoretical safety advantage is of benefit and can help to prevent static buildup or discharge during transfer and loading of fuel. However, the high electrical conductivity can enhance galvanic and electrolytic corrosion of steel, especially in water-contaminated systems. 

Galvanized reinforcement offers significant advantages compared to carbon steel under equivalent circumstances. These include an increase of initiation time of corrosion a greater tolerance for low cover, e. g. in slender (architectural) elements, and corrosion protection is offered to the reinforcement prior to it being embedded in concrete. 

The austenitic alloys are resistant to hydrogen sulfide, chlorides, and moisture. There are also advantages to using stainless steel in combination with other metals. This is tme where the more anodic material has a mnch larger surface area than the cathodic material. For example, galvanic corrosion has not been a problem where stainless steel fasteners are used to hold down aluminum deck plates. This is because the amount of stainless steel (cathodic material) used to hold down the aluminum (anodic material) is quite small when comparisons of surface area ratios are made. Overall, stainless steel has been demonstrated to provide excellent corrosion resistance in severe atmospheric environments. 

This sacrificial anode system does not require the use of an external power source as in the impressed current system. A schematic description is shown in Fig. 12.16. Use is made of zinc and magnesium anodes which corrode and supply electrons to steel bars embedded in concrete. The current flow circuitry is same as in the impressed current system. The anode life is, however, shorter than the life of inert anode. As the current generated by the corroding anode is a function of environment, such as temperature and moisture, it is difficult to adjust and control the current. However, a major advantage is that the risk of over-protection which is inherent in impressed ourrent system is minimized. i.e. operator dependence is removed, advantageously. The galvanic... 

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