What exactly is galvanized steel? If you coat steel or iron with a zinc coating, it can help prevent corrosive substances from interacting the the steel. The coating is thick enough as well to serve as an initial barrier; even if this is scratched, the metal underneath is still protected, and continues to be protected through what is known as galvanic corrosion (a process in which one metal corrodes preferentially when two metals are in electrochemical contact).
How Galvanizing Happens
Today, steel is usually galvanized with zinc using a technique called hot-topic galvanizing. Using this methodology, steel pieces are completely submerged into molten zinc (which is about 840 degrees Fahrenheit).
What?s the Difference Between Galvanized Steel and Stainless Steel?
Stainless steel is a steel alloy that must have a minimum composition of 10.5% chromium. Unlike untouched steel, stainless steel will not easily rust, stain, or corrode after contact with water or other corrosive elements. Stainless steel has been used for everything from buildings around the world (the Jin Mao Building, the Chrysler Building) as well as for bridges (The Helix Bridge, the Padre Arrupe Bridge). It has also been used for several famous sculptures around the world, such as The Gateway Arch. Although 83,000 tons of steel were used to create the Golden Gate Bridge — an incredibly iconic structure — steel has come quite a ways since then, and today, only 50% of that amount of steel would be needed to create the same structure.
It’s not all bridges and internationally famous buildings, however. Many tools are frequently made out of stainless steel as well.
Difference in Applications, Cost as Well
Galvanized steel is popular because it protects steel from corrosion in a wide variety of situations, yet isn?t as costly as stainless steel. For products that will be in constant contact with acids and other corrosive materials, stainless steel is typically the better option. A zinc coating is also not ideal for small nut and bolt pieces; when dipped to galvanize, the zinc often fills in the threads, reducing the efficacy of the pieces themselves. For this reason, most bolts and nuts are made from stainless steel.
So Why Steel?
Not only is steel strong, corrosive resistant, and come in several varieties depending on intended use and budget, but in many ways, steel is a more “environmentally friendly” metal. Steel is one of the most recycled metals on earth and some estimates say that about 88% of steel has been recycled so far!