Can I Use Stainless Steel In Microwave Oven?

Stainless steel is a metal alloy made up of different elements which makes it durable, extremely resistant to corrosion, gives a long-lasting finish, and increases its longevity.

There are different types of stainless steel, and each uses a different combination of elements like chromium, carbon, copper, nickel, titanium, and molybdenum.

Because of its durability and rust-resistant properties, it is used in various kitchen appliances and utensils. 

And since it contains metal alloys, the stainless steel utensils are strictly restricted inside the microwave. 

Stainless steel containers like mugs, plates, bowls, and bottles reflect the electromagnetic waves.

Since the electromagnetic waves emitted by the magnetron can not penetrate through the stainless steel containers to heat the food, it bounces back on the cavity walls, thus increasing the temperature inside the microwave and making the container hot.

This may lead to a spark, possibly cause a fire, or may damage the magnetron altogether.

So it’s best to avoid stainless steel containers and cookware in the microwave.

304 stainless steel is one of the most common types of stainless steel used in kitchens today. It contains chromium and nickel, both of which are highly resistant to corrosion.

That’s why 304 stainless steel is widely used in kitchen utensils like grills, pots, pans, etc., for its anti-rusting or anti-corroding properties.

However, avoid using 304 stainless steel in the microwave. 

Just like any other steel containers, 304 stainless steel utensils are not microwave-safe, and using them in your microwave can damage your magnetron and cause a spark or fire. 

You can put stainless steel spoon in the microwave to stir your food as long as the spoon has round edges, is made of thick steel, and does not touch the inside walls of your microwave. 

Do not use a steel fork or pointy culinary as it may cause a spark. 

Avoid using thin steel spoons because they will melt or cause a fire due to extreme heat inside the microwave oven. 

Also, remember that the steel spoon will get hot very quickly and may burn your hand if you are not careful. Use thick oven gloves to handle the spoon while stirring your food, and after you take it out of the microwave. 

Keep the spoon away from kids and let it reach room temperature before using it with your bare hands. 

No, you should never microwave your stainless steel lunch box. 

The microwave’s heat will cause the metal to warp and can lead to the dangers of burns and fire if they come in contact with flammable material in the microwave, such as paper towels or other items. 

Even if there are no flammable materials inside the microwave, it’s best to avoid stainless steel containers inside the microwave altogether.

Transfer your food into a microwave-safe ceramic or glass bowl to heat your food. 

Brands like Milton now use plastic coating over the stainless-steel lunch box containers making them microwave-safe. 

But this does not mean you should microwave any stainless-steel lunch box with a plastic coating.

Before you start using your new lunch box, check that they are microwave-safe unless the brand mentions otherwise. 

It is recommended that you heat your food in the microwave for no more than 2 minutes at a time. Overheating may melt the plastic coating.

It happened to me once even though I was using a microwave-safe lunch box.

Also, ensure that you remove aluminum foil before heating your food and check that your steel lunch box has no pointy edges. 

Pointy edges of aluminum foil or steel can cause arcing.

You must be wondering what makes plastic-coated stainless steel lunch boxes microwave safe and regular steel lunch boxes unsafe.

Well, the simple answer is – electromagnetic waves emitted by magnetron get absorbed by the plastic and heat it, which in turn heats the stainless steel and thus your food. 

On the other hand, when you use a regular stainless steel lunch box without any plastic coating, the electromagnetic waves reflect from the metal surface and overheat the container and the inside of the microwave, which in turn leads to arcing (spark) and damage your microwave.  

First of all, don’t panic. Switch off the microwave, wear mitten or oven gloves and carefully remove the container or culinary items. 

The container will be hot, so keep it away from your kids’ reach and from accidentally falling on your feet.

Now, as long as your microwave did not cause a spark, it should work fine, and you do not have to worry about the damage. 

If your microwave caused slight arching, turn it off immediately and remove the steel items from the microwave, and your microwave should be fine unless the spark was too bright, which might have damaged the components of your microwave. 

In any case, switch off, unplug the microwave, and remove the steel utensils. Let your microwave cool down before you use it again.

Call a professional to assess the situation more closely if your microwave is not heating or functioning correctly after arcing.