IS STAINLESS STEEL MAGNETIC?

Stainless steel is widely renowned for being a strong and corrosion-resistant metal, but is stainless steel magnetic? This question is slightly more complex. The answer: it depends, because different grades of stainless steel have different magnetic qualities.

Stainless steel does not, in fact, refer to a single type of material. Rather, think of it as an umbrella term for a group of materials that have different qualities and are composed of different elements.

What Are The Different Types Of Stainless Steel?

The three main types of stainless steel are ferritic, martensitic and austenitic.

Ferritic Stainless Steel

Ferritic stainless steel is magnetic as a result of its atomic structure and high concentration of iron. However, it cannot be hardened by heat treatment. Ferritic stainless steel includes grades 409 and 430, which is generally less corrosion-resistant than austenitic steel, but has greater corrosion resistance than martensitic stainless steel.

Austenitic Stainless Steel

Austenitic stainless steel cannot be hardened by heat treatment. It’s non-magnetic, thanks to the presence of nickel. Popular grades, such as 304 and 316 are austenitic and therefore non-magnetic. You’ll see grade 316 widely used in the marine industry, as it’s better able to withstand salt thanks to the presence of 2% molybdenum.

Martensitic Stainless Steel

Martensitic stainless steel can be hardened by heat treatment, and as such is used in instances where strength and hardness are paramount. An example grade is 410, which is commonly used in highly stressed parts. Typically, martensitic stainless steel is magnetic.

Is Grade 304 Stainless Steel Magnetic?

Grade 304 stainless steel is the most popular grade, widely used in a range of applications from commercial appliances to sinks and saucepans. Grade 304 stainless steel is non-magnetic. This is because although it contains 18% chromium, around 8% of the alloy is nickel. It’s the nickel in grade 304 stainless steel that alters its structure and makes it non-magnetic,