Microwave Metal

Microwaves generate oscillating electromagnetic fields at around 2.45 GHz, and when these fields encounter metals, the free electrons in the metal respond by rapidly oscillating back and forth.

Because metals have a high density of free electrons and almost no internal electric field, the microwaves induce strong surface currents instead of penetrating deeply.

These fast-moving electrons can accumulate at edges or points, where the electric field becomes highly concentrated, sometimes creating sparks or plasma if the local field strength exceeds the air’s breakdown voltage.

This rapid excitation and energy buildup explain why metal behaves dangerously in a microwave.