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Accidentally Put Metal in a Microwave – What Happens Now?

People say, ” Here’s a thing that you should never do. Never put any metal inside your microwave.”

Yes, but what happens if you do? Is the result good, bad, or neutral?

Accidentally put metal in a microwave

When you accidentally put metal into a microwave oven, its magnetron will arc the metal, producing bright sparks which are powerful enough to penetrate the oven’s wall and short-circuit the appliance.

Is it dangerous to place metal inside a microwave?

It is not necessarily dangerous, but it is certainly not a good idea.

Metal in a microwave will cause arching.

It is not a good idea to let arcing occur because sparks and electricity could fire anything flammable in the oven, even food.

This happens when the metal touches the oven’s walls, which are themselves made of metal.

Arcing can occur when aluminum foil, silverware items, or stainless steel objects are closer than an inch from the microwave’s metallic walls.

Sparks and electricity can occur in the form of waves to the extent that it burns your food, turning it into charcoal.

Also, stray electricity from the arcing can damage or penetrate the walls and get to the circuitry inside your device.

In summary, aside from the possibility of burning food items, a short circuit can destroy your microwave and render it unfit for use.

Is all metal bad for my microwave, or are there some okay?

All metal is bad for your microwave.

No metal is ‘microwave-safe’ and gets a free pass.

It’s essential that you do not place anything metallic or made of steel in the appliance.

Even aluminum foil can be dangerous.

If the recipe requires you to place aluminum foil in the oven, carefully follow the instructions provided in the recipe to ensure that placing the foil will be used in a way that is known to be safe.

Don’t ignore any foil on containers, metal handles, packaging, or paper plates.

How does arcing occur when there’s metal in a microwave?

Metal is reflective and deflects radiations of radiowaves or microwaves, possibly resulting in all sorts of undesirable consequences, including electrical arcs and sparks.

The interior of the microwave is covered with metal on the inside to make sure that microwaves don’t bounce across the circuitry.

Metal-to-metal contact literally short-circuits this protection. Intense sparks or bolts of electricity easily damage the microwave, which isn’t built to handle this situation.

Any food or item inside the oven stands a good chance of being overheated and severely heat-damaged.

Does metal cause explosions in a microwave?

Metal does not cause explosions in a microwave oven. It is highly likely to cause damage, but it won’t explode.

Films such as “American Hustle” overstate the risks of microwaving stainless steel items or silverware.

Although the film is helpful in highlighting the dangers of putting metal into a microwave oven, ultimately, it turned many people into skeptics when they realized that microwaves don’t explode because someone has left some metal in them.

Thus, it is common to see people online saying there’s nothing wrong with leaving metal in a microwave (!) and think that the risks of microwaving metal are exaggerated.

Why do some people claim it is a hoax that metal is bad for microwave ovens?

Obviously, blasting a metallic object with microwaves for two seconds is a different kettle of fish from blasting it with microwaves for five minutes.

Every extra second the metal is shot with microwaves is an extra second that dramatically increases the possibility of something going seriously wrong.

As such, no one is saying that putting metal into a microwave will 100% damage the appliance, but that fact doesn’t change the point that placing metal items in a microwave definitely can be hazardous.

To ensure that you are safe when microwaving metal or steel that is difficult to take out of the dish (like hot pockets), make sure to keep it at least one inch away from the wall of your oven.

You might get away with the mistake of not removing a metallic fork or spoon from your food or drink because it might be your lucky day, and you’ve dodged a bullet.

Probably, you left the metal further than one inch from the oven’s walls and didn’t run the microwave for very long.

What is the science of metals in a microwave?

Microwave ovens heat items from the inside out by exciting (agitating) water molecules through bombardment with radio-wave radiation.

This is how food gets cooked in your microwave oven.

But what happens to metals? What is the reaction of the metal to microwave radiation?

Absorption and deflection

Metals at the microscopic or the atomic scale are composed of lattice-like arrangements of electrons.

The electrons flow freely between these structures.

Microwave radio waves draw electrons from metals that bounce around in your oven, against the metal mesh on the front of the oven, and against its internal metal walls.

As the electrons zip around, they create heat within the metal, and if this is allowed to go on for too long, the metal becomes superheated.

The thickness of the metal matters

The most serious risk of placing silverware in an oven is that the smaller pieces (like small pieces of aluminum foil or a cheapo stainless steel fork) will heat up quickly, much quicker than a larger, heavier piece of metal. In short order, the metal will become superheated.

Whenever you superheat metal in the microwave, it will wreck your drink, food, even the appliance itself.

You can tell that the metal has superheated when you see it arching.

Frequently Asked Questions About Accidentally Put Metal in Microwave

The walls of a microwave are made of metal, how come that’s not a problem?

The metal in a microwave wall is meant to bounce the microwaves back to the thing being heated. If the thing being heated is metal, this, in turn, bounces the microwaves back to the wall, which bounces the microwaves back to the metal, which bounces the microwaves back to the wall, etc., etc. This creates a feedback loop that can do terrible things like superheating the oven or arching through the microwave oven wall and frying the circuitry within.

Why are pointy metal objects even more dangerous to a microwave?

If the metal you place in the microwave is sharply pointed (like forks) or has sharp edges (like aluminum foil that has been crumpled) or is very thin (like the gold-colored decoration that you see on some fancy cups), the electrons that are moved around by the microwaves may clump up around the edges. If too much charge accumulates in one place, those electrons become extremely “uncomfortable” and leap into the air to try and find a less crowded spot. That leaping into the air is what we see as sparks and arcing.

Afterword: Accidentally put metal in a microwave

Arcing is what occurs when you accidentally put metal in a microwave.

Arcing happens when things made of metal, such as silverware or packaging foils made of metal, are exposed to radio waves or electromagnetic waves generated by the magnetron in your microwave oven.

The result is sparks and an electrical current that is generated throughout the metal.