Stainless steel is a popular material used for projects large and small.
If you have a particular project in mind and you’re considering using stainless steel, then you may wonder if it has magnetic properties.
Here’s what you need to know about whether stainless steel is magnetic or not.
Is Stainless Steel Magnetic?
Yes, some grades of stainless steel are magnetic.
Some grades of stainless steel are also not magnetic.
For something to become magnetic, it needs to have a certain amount of iron in it.
Stainless steel usually contains some amount of iron.
However, not all grades have enough iron to give them a strong magnetic field.
As a result, while some grades may show some magnetic qualities, they aren’t magnetic in the sense that other grades of stainless steel are.
Here are the following grades of stainless steel that are magnetic:
The grades that aren’t magnetic are those made with austenite.
Grades 409, 430, and 439 are ferritic stainless steel.
They contain high levels of iron which make them highly magnetic.
Grades 410, 420, and 440 are martensitic stainless steel.
Martensitic stainless steel has magnetic properties because its crystal structure can become ferromagnetic.
It also contains high levels of iron.
Austenite stainless steel isn’t magnetic because it doesn’t contain high levels of iron.
It contains high levels of austenite instead which does not create a magnetic field.
That said, if an austenite stainless steel piece goes through thermal treatment, then it might display some magnetic properties.
That’s because, through the thermal treatment, certain parts of the steel can actually form ferrite.
It’s the bit of ferrite that forms that becomes magnetic.
As such, stainless steel is, in most cases, magnetic.
Can Magnets Stick To Stainless Steel?
Yes, some magnets can stick to stainless steel.
It all depends on the grade of stainless steel.
For example, if you’re trying to stick a magnet on 409-grade stainless steel, then the magnet will stick to it.
However, if you’re trying to stick a magnet to 304-grade stainless steel, then the magnet won’t stick to it.
That’s because 304 stainless is austenitic stainless steel.
The more ferrous the grade of stainless steel is, the more likely the magnet will stick to it.
Why Isn’t The Magnet Sticking To Stainless Steel?
If you’re trying to put a magnet on your stainless steel appliance and it isn’t sticking, then you may wonder why.
It’s likely because the stainless steel appliance contains some alloy mixture that inhibits the magnetic properties.
For example, the stainless steel appliance may be made of a mix of stainless steel, nickel, manganese, carbon, or even austenite.
As a result, there isn’t much iron in the alloy.
Since there isn’t much iron, there’s nothing generating the magnetic properties.
The magnet slides off rather than sticking to the appliance.
How Can You Tell If The Stainless Steel Is Real?
Whether you’re buying an appliance, a piece of jewelry, or something else that contains stainless steel, you may wonder if it’s real.
Because stainless steel is quite durable, you might wonder if what you bought is authentic.
Here are a few ways you can tell if what you have is real stainless steel.
1. Look For Codes
One way to sometimes determine if something is made of stainless steel is to look for a code.
You should see a four-digit code somewhere on the piece.
This is a code that ASTM International, which used to be known as the American Society for Testing and Materials, uses to identify the piece.
Not every piece will have a code.
For example, if you’re buying a piece of jewelry, then the artisan might not include the code since it could ruin its beauty.
However, for industrial purposes, you can often find the code printed somewhere on the material.
You can then use this code to look it up and determine if the ASTM identifies it as stainless steel or not.
2. Run A Magnet Over It
Another way that you can test to see if the object you have is made of stainless steel is to use a magnet.
Since there are different grades of stainless steel, this test might not be perfect for every application.
However, in many cases, you can tell if it’s real stainless steel with a magnet.
The biggest problem comes when testing stainless steel jewelry.
To save money, some jewelers will mix their stainless steel with another alloy that isn’t magnetic.
Aluminum is a popular choice.
Since aluminum isn’t magnetic, if there’s a large amount of it in the alloy, then it will make the object not magnetized.
It may technically have stainless steel in it, but it might have more aluminum than stainless steel.
That said, you can run a magnet over the object or material.
If it sticks, then there’s a good chance that it has stainless steel in it.
If it doesn’t stick, then it might still have some stainless steel in it, but it might be a low quantity.
It might also not have any stainless steel in it at all.
3. Look For Rust
Another way to test the object or material to determine if it uses stainless steel is to look for rust.
One of the defining features of stainless steel is that it doesn’t rust.
That makes it a bit different than iron, for example, which is very susceptible to rusting.
That isn’t to say that stainless steel can’t rust at all.
Since it does contain some iron, it can rust with enough time and exposure.
However, it usually has other alloys within it that help protect against corrosion.
Take the time to perform a visual inspection of the object or material.
If you see rust, then there’s a good chance that it isn’t made of stainless steel.
However, the rust could also just be on the surface and caused by the oxidation of other alloys within the piece.
To determine if this is the case, you’ll want to make a mixture of 1/2 nitric acid and 1/2 hydrofluoric acid.
Dip a rag into the mixture, then wipe down the item’s surface.
If the rust comes away and you don’t see any corrosion on the object, then there’s a good chance that it’s stainless steel.
However, if you wipe it away and you see that the object has rusted through, then it is not stainless steel.
4. Use Muriatic Acid
One of the most dangerous tests that you can do to determine if the object or material is stainless steel is to test it with muriatic acid.
Since you’re going to be handling an acid, you’ll want to make sure that you have all the safety gear you need.
For example, you’ll want to have safety gloves, safety goggles, and the right kind of glass.
You should also research the proper procedures for getting rid of the acid after you’re finished testing with it.
Once you’re ready to perform the test, you’ll need to get your hands on muriatic acid and a dropper.
Keep in mind that if the test is a success, the object or material will have a permanent marking on it.
As such, if you’re testing on something like a piece of jewelry, then you’ll want to perform the test in an area that isn’t usually visible.
For example, the inside of a ring or the back of a necklace.
Using the dropper, suck up a bit of the muriatic acid.
Then place a single drop on the material.
Let it rest for a few seconds, then wipe it off carefully.
If you see an area that is now discolored, then you have a real piece of stainless steel.
A final test that you can perform to determine if something is stainless steel or not is to clean it.
Stainless steel has a reputation for being mirror-like and very shiny when cleaned.
Since other types of metals also share this feature, it’s worth performing this test in addition to some of the others listed above.
Take a rag and give the piece a good clean.
If you notice that it’s shiny and mirror-like, then there’s a good chance that it’s stainless steel.
Look for a dull appearance even after you cleaned the item.
For example, if it still looks cloudy after you cleaned it, then there’s a very good chance that the material isn’t stainless steel.
Does Stainless Steel Rust?
No, stainless steel doesn’t rust in the sense that it’s visible.
That said, there is some form of corrosion that can occur on the surface of stainless steel.
As Michael L. Free, a metallurgist engineer, explains, certain alloys within stainless steel create a thin layer of corrosion.
However, the film also keeps oxidizing reactions from occurring below this layer.
As such, the amount of corrosion that the naked eye perceives is so low that it is basically invisible.
Without this protective layer, corrosion can begin to occur.
It eventually will become thick enough that the eye perceives it as rust.
The alloys involved in making the protective layer of corrosion include:
It can also sometimes contain nickel and molybdenum.
Chromium, in particular, reacts with oxygen and enables the material to create a protective layer.
Since chromium keeps water and oxygen from getting deeper into the material, it keeps corrosion from forming as well.
As such, stainless steel doesn’t appear to be rusting.
Why Is Stainless Steel Worth Using?
If you’re planning a project or want to buy something made out of stainless steel, then you’ll usually find that it has a higher price compared to other materials.
You may wonder if this higher price is worth it, especially if you’re on a budget.
Here are a few reasons why it’s worth spending a bit more money to use stainless steel.
One of the primary reasons why stainless steel is worth the money is because of its corrosion-resistant properties.
If you need a fence or some other structure outdoors, then you must consider water exposure.
Something is inevitably going to become exposed to water if it spends all its time outside.
When other types of metal are exposed to water, they start to oxidize and become corrosive.
They start to rust.
As metal rusts, it becomes weaker and weaker.
That’s because its materials are slowly breaking down and crumbling.
After the corrosion grows and expands enough, it’s possible that the structure or object could collapse.
If this structure was a fence, for example, then it would fall to the ground and no longer serve its function.
Stainless steel has a protective layer on its surface which inhibits corrosion.
As such, it’s safe to use for most outdoor applications.
It’s worth the extra money because you’ll build something that stands the test of time.
If you chose cheap fencing materials, then you may find that you need to replace them every few years.
You won’t be saving money in the long run because you’ll be spending money to replace the fence.
At some point, the amount that you spend is going to surpass the amount that you would have paid for a stainless steel fence.
While stainless steel may cost more initially, it will save you money down the line due to its corrosion resistance.
Stainless steel is worth the money because of its corrosion resistance.
2. Stain Resistant
Another reason stainless steel is worth the extra money is because it’s stain resistant.
This means that if something gets spilled on its surface, you can wipe it away without it seeping into the material and creating a stain.
That isn’t the case with other porous materials like wood and carpet.
If you were to spill wine, for example, on a wooden counter, then the liquid would seep into the wood.
You might be able to clear off the surface stain, but the liquid that is absorbed into the wood will always leave a permanent stain there.
It might mar the counter’s appearance enough that it needs to be replaced.
If the counter is made of stainless steel, then you wouldn’t have this problem.
That’s because the protective layer that coats the surface of stainless steel reduces its porosity.
If you were to spill wine on it, then the protective layer would keep the wine from seeping deeper into the material.
As a result, when you clean the wine off, you won’t see a stain beneath it.
This makes stainless steel a great material for places where stains or messes are inevitable.
Homes with children, for example, can benefit from having stainless steel appliances and other pieces of furniture.
Certain industries, like healthcare, can also benefit from using stainless steel products and surfaces.
Stainless steel is worth the extra money due to its ability to resist stains.
3. Long Lifespan
One of the reasons why stainless steel can sometimes be expensive is its longevity.
Stainless steel is quite durable.
Its corrosion resistance is part of the reason why it’s so durable.
While other materials start to fall apart from rust, stainless steel remains intact.
It’s also quite strong.
It takes more force to break stainless steel than other materials.
Because of this, manufacturers tend to put a higher price tag on this material.
They know that when someone buys a stainless steel product, they’re probably not going to be in the market for that same product for some time.
They have to price items so they make the most money possible from that single sale.
For example, if someone buys a stainless steel dishwasher, they usually end up getting another one because they want upgraded features or because the electronics have malfunctioned.
It’s rarely because the frame of the dishwasher has failed.
Stainless steel is worth it because it has a very long lifespan.
It may even outlive you.
Stainless steel contains iron which makes it magnetic, although some grades don’t contain iron.
You can use a magnet test, among others, to identify stainless steel.
If you’re still on the fence about whether stainless steel is right for you, the reasons listed above can help you make your decision.