Why do microwave ovens produce sparks when using metal utensils?

The question of why sparks occur when using metal utensils in microwave ovens, microwave ovens are heated by using electromagnetic waves and water molecules in food.

This works between the poor conductors of water, and the energy of the microwave only heats up the water molecules.

Normally, and metal is a good conductor, then the electromagnetic wave will produce a short circuit discharge phenomenon and sparks, so when the microwave oven uses metal utensils, electric sparks will be generated.

Microwaves interact with metallic materials.

When microwaves interact with a metallic material, the electrons on the surface of the metallic material will shake back and forth. If the metal is smooth overall, this will not cause any problems. However, if there is a sharp part, such as in the tines of a fork, the charge can build up, resulting in a high voltage.

If the voltage is high enough, it may rip an electron from a molecule in the air, creating sparks and ionized (i.e., charged) molecules. Charged particles absorb microwaves more forcefully than water, so once a spark appears, more microwaves will be absorbed by the charged particles, resulting in more molecular ionization, so that the spark becomes a fireball.

Overall, he's a good person, and he's written so much, but there's a lot of mistakes.

As for the question of why there is an electric spark when heating metal, well, although the contemptible person studies the electromagnetic field, the microwave oven has never been within the scope of our professional research... Electric sparks, naturally the air is broken down by high pressure, so how does high pressure come about? . . A resonator will be formed in the microwave oven, and the energy of the electromagnetic field in it will continue to accumulate, and the amplitude of the electric field will continue to accumulate until the voltage value is too large, and the air will be penetrated.

Then, the microwave oven itself will naturally avoid this when it is designed. Then, after you put in a metal, it will change the working mode of the resonator, then, in some places, the voltage will be too large to break down the air The above is just a personal opinion, please correct.

Agreed, but be aware that metal placed in the microwave does not necessarily ignite and discharge. Metal with a relatively large geometry and a sleek shape will not be discharged, otherwise the furnace wall will be metal. The discharge is generally small in size, such as the gold edge of porcelain; Or there are shapes that tend to cause tip discharge, such as aluminum foil (especially wrinkled) or metal forks.

Causes:

Microwaves cannot penetrate metal objects, but are reflected back, and some of them will excite metal electrons to oscillate and generate electric current.

If the food is heated in a microwave oven with metal utensils, 1) the food cannot be heated because the shielding effect of the metal blocks the microwaves, and (2) the discharge sparks between the metal utensils and the furnace body are generated due to the microwave excitation of electrons in the metal to generate an electric current, which will burn the furnace or utensils in serious cases.

Correct handling method: If such a situation is found, the power should be cut off in time, and then the fire source should be extinguished.

There are many reasons for microwave oven sparks, such as the presence of metal parts in the container, which can occur when the microwave oven is used. In addition, if tin foil is used when heating food, it can also cause sparks in the microwave. Therefore, when using the microwave oven to heat food, be sure not to use items that do not meet the requirements.