Which Metals Cannot Be Used in the Microwave?

Ever blew up a microwave before or heard a story about it? In most cases, this happens when someone has used a metallic dish inside the microwave. Repairing such a microwave costs high and on many occasions, it was found out that such microwaves cannot be repaired and would have to be replaced with newer ones. 

Before you end up making any mistake, make sure you keep all the following items away from the Microwave. We also reviewed some microwave-safe dishes so that you can purchase the best ones and not worry about your microwave blowing up someday. 

Why Are Some Dishes Not Microwave-Safe?

This mainly depends on the material with which these dishes have been made from. Some materials are acceptable while others aren’t. Let’s go on each of them one by one. 


We have good news and bad news for people, who wanted to microwave a ceramic cup, plate, or any other item. The good news is that using ceramic in a microwave will not blow up the microwave or cause it any damage. However, the bad news is that it might end up burning your hand to a very bad extent. 

Why? Because ceramics can get scorching hot from the microwave and you will not be able to hold the cup. Moreover, in certain ceramics, the dish could get scorching hot while the contents inside it may not heat up as much because ceramics conduct all the heat. Instead of the microwaves passing through the content of any mug, the microwaves are only in a reaction / inter-reaction state with the ceramic. 

Use your oven wisely.


Sorry metals, your entry is banned to microwave ovens, forever! This statement should be taken seriously because if you try to microwave any metallic items such as steel glass, plates, forks, knives, spoons, or other items, there is going to be a major fire in the oven which may get worse. 

The metallic walls of the inside of the microwave oven are made for safety so that microwaves do not go out of the oven. The inside metal is also made with the purpose to reflect the waves on the food to warm it up. But if there is any kind of metal inside, the waves will be reflected causing the electron particles to be highly active and charged. This causes a significant threat for starting out a fire.  

Plastic Containers

With a very high amount of heat being disseminated from the microwaves at one particular instance, there is a high chance that a foam plastic container can simply melt away. The food will be heated but you certainly don’t want your plastic container to be melted in the worst possible condition. Foam containers can melt but many other hard plastics will not melt in a microwave which will make them safe for use. 

Anything with Aluminum Foil

One can love fireworks but not when they are coming out of a microwave. For this reason, having any item with aluminum foil on it should not be heated in a microwave. And yes! Aluminum Foil is a kind of metal too. Since the inside of a microwave is made out of metal, the two can interact with electricity flowing through different pieces of metal and ultimately igniting a fire. 

Aluminum Vessel in a Microwave

For those who are wondering if the aluminum containers have any different treatment in a microwave, yes, you are right. According to a study conducted by the European Aluminum Foil Association, it was found out that aluminum containers can suit perfectly for microwave cooking when particular guidelines are followed. 

This means that you should only use your microwave with aluminum vessels or containers when it is in convection mode. Using or trying out other modes may spark flames in the microwave, and that’s the least anyone would want. 

Metal containers are not allowed in a microwave oven, but an aluminum container is totally fine..

Shopping and Paper Bags

Shopping Bags such as the ones that warm up quickly and might melt down are the ones that shouldn’t be microwaved. This is because when they melt down, they can stick to the food item that you are microwaving. Typical paper bags do not have any kind of susceptors to consume the radio waves which is why they may catch fire and burn with intense heat coming in rapidly. 

Many of you might be thinking why this hasn’t occurred to you anytime when you microwaved a popcorn paper bag. A simple explanation for this is that these bags have susceptors that can consume radio waves which not only cook the popcorn for you but also ensure maximum safety to the users. 

Hot Peppers

That may not be a dish but something very severe and could cause an intense reaction to the human body if exposed. The hot peppers must not be microwaved because if you do so, you might end up burning your eyes or choke right away because of the chemicals being released from the peppers. You will feel just as if you have been pepper-sprayed giving you a sore neck and burned eyes. Moreover, there can be a firm in the oven too and no one wants that. 

Styrofoam Containers

Some containers are safe but not the ones which are made out of Styrofoam. They are made out of polystyrene and may begin to melt right when you start microwaving them. Not only will this melted mixture come directly on your food, but you will have a big mess in the oven to take care of. 

Chemicals can also be released into the food making it hazardous and not completely safe for eating. On the other hand, many modern polystyrene foam containers have been made microwave safe allowing you to warm up all the food instantly.

Also Read – What is a magnetic field flip?

Metal is highly reactive to microwaves and can reflect the waves back.


The definite answer to the question of metal usage in microwaves is that “It should never be done”. Using metals in a microwave can turn out pretty bad so don’t try to do it anyhow. There are plenty of other alternatives such as using the different types of microwave-safe containers or bowls. Make sure that the other items such as ceramics are also not safe to be put in a microwave so keep them away if you don’t want any fire.