Stainless Steel “The Basics"
- The most important alloying element that makes stainless steels “Stainless" is Chromium.
- When at least 11% Cr is present, a continuous layer of an invisible oxide will form, which is what gives stainless steels their superior corrosion resistance.
- Nickel is the most commonly talked about element in stainless steels, due to the effect on price. The main role of Nickel in 200 and 300 series grades is to help create an austenitic structure which provides favorable mechanical properties.
Type 304 Stainless:
This alloy is the most frequently used alloy in the stainless steel family. These alloys may be considered for a wide variety of applications where one or more of the following properties are important:
- Resistance to corrosion
- Prevention of product contamination
- Resistance to oxidation
- Ease of fabrication
- Excellent formability
- Beauty of appearance
- Ease of cleaning
- Ready availability of a wide range of product forms.
- Alloy is non-magnetic
This alloy is used widely in equipment and utensils for processing and handling of food, beverages and dairy products. Heat exchangers, piping, tanks and other process equipment as well as dump bodies and truck trailers. Exposure to Hydrochloric or sulfuric acid at elevated temperatures is too aggressive for this alloy.
Finishes: (Only 2B and #4 finishes are available at Williamsen)
- HRAP –Is a hot rolled annealed and descaled product resulting in a dull rough surface. It is available in plate and sheet and is used for functional applications where a smooth decorative finish is not important.
- 2B – A smooth, moderately reflective cold-rolled annealed and pickled or descaled finish typically produced by imparting a final light cold-rolled pass using polished rolls. This general purpose finish is more readily polished than a HRAP finish product.
- #3 Polished Finish – A linear texture finish that may be produced by either mechanical polishing or rolling. Average surface roughness may be up to 45 micro inches.
- #4 Polished Finish – A linear texture finish that may be produced by either mechanical polishing or rolling. Average surface roughness may be up to 35 micro inches.