Most of the time people get confused about the difference between magnetic & nonmagnetic stainless steel. According to their properties, SS metal is categorized into magnetic & non-magnetic features & they present with specific specifications, features & uses. In simple, we can say metals the attract by magnets are magnetic metals & those who didn’t attract by magnets are non-magnetic metals. Magnetic stainless steel has more chromium and molybdenum, as well as Non-Magnetic steel keeps better corrosion resistance than the common magnetic grade. Its stainless steel grade atoms are lined up in a crystal structure. Magnetic materials contain iron and come down to the microstructure of the steel. And non-magnetic substances contain a high amount of austenitic. Both are widely used for industrial purposes.
Now, let’s discuss in brief the magnetic and non-magnetic stainless steel comparison and their types. I hope this blog will be useful for understanding magnetic and non-magnetic stainless steel.
Magnetic Stainless Steel & Types
The magnet is used in a testing process to verify the composition of stainless steel. And this is important to prove the stainless steel. Magnetic Stainless Steels are those Steels that are not free from the Magnet test. Below are some magnetic stainless steel types.
- Duplex Stainless Steel- This Stainless steel is one of the most recent alloys, it offers an easy fabrication, excellent balance of corrosion resistance, and price savings, just because of the non-appearance of nickel. It has a two-phase microstructure of ferrite grains and austenite. Mainly designed to provide better corrosion resistance, chloride stress corrosion, and chloride pitting corrosion, and also stainless steels such as type 304 (it contains 8% nickel and 18% chromium) and 316 (it contains 10% nickel and 2% molybdenum).
- Ferritic Stainless Steel- Ferritic Stainless Steel is also a family of stainless steel, this is the most cost-effective family of stainless steel. It has magnetic properties due to the alloy’s large ferrite composition. This Stainless Steel, by contrast, is arranged as a body-centered (bcc) lattice. Atoms are arranged in the corners of the cube and another single one is located in the center of the cube. Most likely Bcc crystal is made up of Silicon, chromium, and molybdenum.
- Hot Rolled Steel- This stainless steel has roll pressed at extreme temperatures, which makes the steel easier to form, show the results of the product, and is easy to work. After this process, hot-rolled steel shrinks slightly as it cools. It is ideal for magnetic steel where tolerances and precise shapes are not as important. Mostly used in construction and welding trades for making I-beams and railroad tracks. It has extreme tensile and yield strength.
Non-Magnetic Stainless Steel & Types
The Magnet Test of stainless steel is not accurate, because it depends on the stainless steel’s composition. Because it consists of austenitic, aluminum, and copper, then recognized as stainless steel. There is some stainless steel that has less or lacks magnetic properties. These are the following types of non-magnetic stainless steel:
- Austenitic Stainless Steel- Austenitic stainless steels contain nickel and are non-magnetic. If the alloy is austenitic crystal structure in nature, then it’s non-magnetic. Rich in strength, durability, and corrosion resistance. This stainless steel is environmentally friendly, easy to produce, clean, and maintain. Alloy is used as a structural component in present and future nuclear reactor systems. Widely used in many industries including automotive, aerospace, industrial applications, and medical.
- Aluminum- This is a non-magnetic metal similar to lithium and magnesium. Under normal circumstances, aluminum nature has no visibly magnetic on the other hand high enough magnetic fields most matter will exhibit some magnetic attraction. Useful for many applications because of its machinability, strength, heat treatability, corrosion resistance, and weldability. This steel has many uses such as aircraft components, decorative hardware, brakes, marine fittings & hardware, electrical components, hydraulic pistons, pins, bicycle frames, and valves.
- Copper- Copper is a non-magnetic metal, with no magnetic properties. It is a few metallic elements with a natural color. It has a reddish-gold metal combined with bronze alloy. It has high electricals due to its electrical conductivity. Commonly used in creating coins, and conductor of heat and electricity. It can also interact with magnets. It doesn’t react with water, but slowly reacts with atmospheric oxygen and protects the underlying metal from corrosion.
Conclusion
For Stainless steel to be magnetic, the alloy’s crystal structure must be arranged in a ferritic or martensitic structure. And also the alloy must have iron in it. On the other hand, austenitic stainless steel contains nickel and if the alloy has a crystal structure of austenitic, then it’s not magnetic. Simply, duplex, ferritic & hot rolled steel is magnetic stainless steel and austenitic, aluminum, and copper is non-magnetic stainless steel.