Galvanized Steel Frames
Galvanized steel is steel that has been coated with a thin layer zinc to help resist corrosion. This thin layer of zinc may be applied by hot-dipping or electro-galvanizing. In hot-dipping, steel is dipped in a bath of hot liquid zinc. When removed, the steel cools and the zinc coating adheres to the steel. This creates galvanized steel. When steel is placed in an electrolyte bath of zinc, the electrogalvanized coating of zinc hardens to create a thin, bonded layer. Both methods are good for creating a thin, corrosion resistant layer of zinc over the steel.
Galvanized steel has many uses, due to its rust resistant characteristics. Most nails, nuts and bolts are made of galvanized steel as are parts of household appliances which may experience exposure to water. Galvanized steel is also often used in ornamental fencing. Some framing in domestic residences is made of galvanized steel.
Galvanized steel has its limits. For example, if it is likely that salt water or salt spray will be in the area where steel is needed, galvanized steel should not be used as the salt interacts with the zinc in the coating and will eventually result in oxidation.
Stainless Steel Frames
Stainless steel is created by adding a minimum 10% chromium concentration to molten steel. This modified steel is then shaped and allowed to cool. As the steel cools, it hardens and stainless steel is formed. The steel is often “pickled” with acid treatments to remove impurities on the surface of the steel and to accomplish passivation to form a non-corrosive layer on the steel.
Advantages of Stainless Steel Frames
Stainless steel is the primary metal used in construction. It is very strong and resistant to rust. Stainless steel is a popular choice for applications where salt or salt spray may be present. It is excellent for all wet environments. The one environment that is not friendly to stainless steel is where chlorine is present. Chlorine eats through the oxide layer of the stainless steel leaving it vulnerable to oxidation.
Stainless steel is extremely strong. It is used where strength and corrosion resistance are required.
As an example of the relative strength of Stainless Steel compared to Low Carbon Steel, in one test, the Tensile Strength (MPa) of the Stainless Steel sample was 595.49, whereas that of the Low Carbon Steel was 290.71. The Percentage Total Elongation at Fracture (%) of the Stainless Steel sample was 84.290, whereas the Low Carbon Steel sample measured 44.981%. The Maximum Load (N) of the Stainless sample was 9441.3, compared to 4585.4 from the Low Carbon sample.
The use of Stainless Steel in safety shower cubicle frames results in a much stronger, more durable frame and is highly desirable, except in environments where chlorine may be present in high concentrations.