Introduction
Galvanic corrosion is a type of corrosion that occurs when two different metals are in contact with each other in the presence of an electrolyte. In this article, we will discuss the galvanic corrosion between stainless steel and galvanized steel.
What is Galvanized Steel?
Galvanized steel is steel that has been coated with a layer of zinc to protect it from corrosion. Zinc is a sacrificial metal that corrodes instead of the steel when exposed to the environment.
What is Stainless Steel?
Stainless steel is a type of steel that contains at least 10.5% chromium, which gives it its characteristic resistance to corrosion. It is widely used in various industries due to its durability, strength, and resistance to rust and staining.
Galvanic Corrosion
When stainless steel and galvanized steel are in contact with each other, galvanic corrosion can occur. This is because stainless steel and galvanized steel have different electrochemical potentials. The more noble metal (stainless steel) will act as a cathode, while the less noble metal (galvanized steel) will act as an anode. The anode will corrode faster than it would if it were not in contact with the cathode.
Preventing Galvanic Corrosion
There are several ways to prevent galvanic corrosion between stainless steel and galvanized steel:
- Use a non-conductive barrier between the two metals
- Use a less noble metal for the galvanized steel
- Isolate the two metals with a dielectric union
- Use a sacrificial anode with the galvanized steel
Applications
Galvanized steel and stainless steel are widely used in various industries, including construction, automotive, and manufacturing. Some applications include:
- Structural components
- Piping and tubing
- Furniture and fixtures
- Automotive parts
- Food processing equipment
Conclusion
Galvanic corrosion between stainless steel and galvanized steel can be a costly problem if not properly addressed. By understanding the nature of galvanic corrosion and taking preventative measures, it is possible to avoid corrosion and ensure the longevity of structures and equipment.
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