The coating inside a microwave oven is designed to reflect microwave radiation rather than absorb it. The purpose of the coating is to prevent the microwaves from escaping the oven and causing potential harm to people or interfering with other electronic devices.
The material used for the coating is typically a conductive metal, such as aluminum. This metal coating reflects the microwaves back into the oven cavity, allowing them to be absorbed by the food or other items being heated. The reflective nature of the coating helps to distribute the microwaves evenly and ensures efficient heating.
It's worth noting that while the coating is highly effective at reflecting microwaves, it is not completely perfect. Some small amount of microwave radiation may escape through the door or other openings, which is why it's important to have a properly functioning microwave with a well-sealed door.