2. Because the aluminum box can reflect the microwave, it can't penetrate and absorb it, so the food inside can't be heated, and the metal box cover is close to the metal box body, which is easy to cause fire or even explosion. When heating, we need to choose a suitable container and put it in a microwave oven, usually tableware made of traditional ceramics and high-temperature glass or a special microwave oven to heat the container.