Classifications of Stainless Steel
Stainless steel alloys are generally divided into five classes, each designated by the metallurgical characteristics and phases within its microstructure, including:
- Austenitic
- Martensitic
- Ferritic
- Duplex
- Precipitation Hardening
Austenitic vs. Martensitic Stainless Steels
Austenitic stainless steels are the most weldable of the groups and can be sub-divided into three groups: common chromium-nickel (300 series), manganese-chromium-nickel-nitrogen (200 series) and specialty alloys. Austenitic is the most popular stainless steel group and is used for numerous industrial and consumer applications, such as in chemical plants, power plants, food processing and dairy equipment. Although generally very weldable, some grades of austenitic stainless steel can be prone to sensitization of the weld heat-affected zone and weld metal hot cracking.
In contrast, martensitic stainless steel types (such as 403, 410 & 420) have a body-centered cubic crystal structure in the hardened condition. This type of hardened condition makes martensitic stainless steel types much more difficult to weld. When attempting to obtain useful properties and prevent cracking, martensitic stainless steel varieties usually require preheating and post weld heat treatment. Martensitic stainless steel can also be held at an intermediate temperature for various times, in a process called tempering, which reduces strength but vastly improves toughness and ductility.
Stainless Steel Grades
Stainless steel raw material grades are based on the types and amounts of elements found within the stainless steel. As your premier stainless steel metal supplier our grades of stainless steel, include:
304 Stainless
304 Stainless is one of the most widely used of all the stainless grades. It is non-magnetic, has excellent formability, and is easy to weld. 304 Stainless is also called “Fresh Water” grade or “Food Grade” because of its extensive use in the food industry. FYI, another name for 304 Stainless is 18/8 stainless and this designation can often be found on the back of utensils.
316 Stainless Steel
316 is a grade of stainless that is sometimes called “Marine” grade or “Pharmaceutical” grade. 316 stainless steel raw materials have better corrosion resistant properties than 304 and is commonly used in pools with chlorine or salt water. 316 stainless steel raw materials also provide excellent forming and welding characteristics.
Stainless Steel Varieties
As your premiere stainless steel metal supplier our inventory of stainless steel products, include:
- Stainless Steel Sheets
- Stainless Steel All thread
- Stainless Steel Angle
- Stainless Steel Bar Stock
- Stainless Steel Channel
- Stainless Steel Pipe & Round Tube
- Expanded Stainless Steel
- Sheet & Plate Stainless Steel
- Stainless Steel Rectangular & Square Tube
Have questions,
request a quote on M & K Metals stainless steel raw materials, stainless steel sheets, stainless steel angle or other stainless steel profiles you need. Call us at our Gardena, Los Angeles location at
800-870-6382, or
contact M & K Metal Co. for more information.