Austenitic Steel is a non-magnetic form of Stainless Steel. They possess a range of beneficial chemical and mechanical characteristics and are the most commercially popular alloy group within the Stainless Steel family. Austenitic Stainless Steels get their name from the high temperature form of Iron with Carbon in solid solution, known as Austenite, which is non-magnetic. Traditionally, Austenitic Stainless Steels have an 18% chromium, 8% Nickel Alloy content, commonly known as 18/8 Stainless. As a group, they have excellent toughness and good formability. Increasing the Chromium and Nickel content, increases corrosion resistance. Increasing other elements, such as Molybdenum, can also further improve corrosion resistance. Austenitic Stainless Steels are not heat treatable. However, cold working can improve their mechanical properties, including strength, hardness, and stress resistance.
The most common Stainless Steel among Manufacturers are the Austenitic 300 Series Alloys. These alloys offer the full range of possibilities available when altering alloying levels. In the fully annealed condition, they are essentially non-magnetic. Nonetheless, cold working of the less alloyed grades will induce structural changes leading to increased levels of magnetism. Grades with a lower Carbon content are identifiable with the addition of the “L” after their name. The cost of 300 Series fluctuates due to the availability and cost of Nickel.
200 Series Alloys contain a lower Nickel content and additional Nitrogen. Consequently, this makes 200 Series Stainless Steels a lower cost alternative to the 300 Series.