Do magnets stick to stainless steel?

Sometimes. It depends on the kind of stainless steel. SSINA says ferritic grades such as 409 and 430 are magnetic, while austenitic grades such as 304 and 316 are non-magnetic when annealed, though cold worked material may be somewhat magnetic. Whirlpool says a fridge may not hold magnets if it’s made of austenitic stainless, or if a coated finish leaves your magnets too weak to reach the steel.

Which stainless grades a magnet sticks to

Why your stainless fridge won’t hold a magnet

Whirlpool gives two reasons. The fridge may be made of austenitic stainless, which it says is non-magnetic because the iron is alloyed with nickel, manganese, carbon and nitrogen. Or, if the fridge has a coated finish, the magnets you’re using may not be strong enough to reach the steel at its core.

Goudsmit Magnetics says the grade is why a magnet sometimes sticks to a stainless fridge and sometimes doesn’t. It adds that this says nothing directly about the quality of the steel, mainly about its makeup and structure.

Where the sources differ on 304 and 316

• Whirlpool calls grades 304 and 316 non-magnetic, with no exceptions given.
• SSINA says austenitic grades are non-magnetic in the annealed (heat-treated) condition, but cold worked and cast material may be somewhat magnetic.
• K&J Magnetics lists 304 as “Not magnetic, or a little magnetic after cold work (bending, deforming, etc.)” and 316 as not magnetic.
• Goudsmit Magnetics says austenitic grades are usually non-magnetic or only weakly magnetic, and that forming, welding or cold working can make them locally slightly magnetic.

Black stainless steel

Whirlpool says magnets stick to black stainless only in certain cases: the steel at its core has to be ferromagnetic, and the finish’s coating has to be thin enough for a magnet to cling. If fridge magnets matter to you, it suggests doing your research before choosing a finish.

How to tell with your own fridge

K&J’s answer is to try it, since good magnetic data on every kind of steel is hard to find. Goudsmit says a magnet test is useful as a first indication but isn’t always enough to identify a material precisely. Neither one names the grade any fridge brand uses, and we couldn’t find a fridge maker that does.

Keeping magnets from scratching the finish

• Shape: Whirlpool says magnets with sharp corners or textures may scratch, and suggests flat vinyl magnets that sit flush. K&J says magnets that are rigid or have sharp corners can dig into the fridge coating.
• Strength: K&J says magnets that are too strong may scratch the surface just by sliding around or during removal, and that its steel-cup mounting magnets are harder than the fridge coating and may leave scratches if moved around carelessly.
• Clean first: K&J says dust on the door gets sandwiched under the magnet and can dig into the coating.
• A soft back: K&J suggests a magnet cushion pad, a thin plastic sticker or a coating on the back of the magnet.

K&J’s FAQ says magnets should not harm a refrigerator, stove, oven or microwave.

K&J Magnetics, which sells neodymium magnets, says they are not toys and that if several are swallowed they can attach to one another through the intestine walls. The CPSC says that if you suspect magnets have been swallowed, seek immediate medical attention. We’d keep small strong magnets away from children. K&J also warns that the strong fields near a neodymium magnet can affect pacemakers, ICDs and other implanted medical devices.