Electrical breakdown

Electrical breakdown is the abrupt loss of an insulating material’s ability to resist current under a strong electric field, producing a conductive path.

Avalanche breakdown: A breakdown process in which charge carriers gain energy from an electric field and create more carriers by impact ionization. Carrier multiplication drives the sudden conductivity increase in gases and semiconductor junctions.
Electric field: A vector field that describes the electric force per unit charge at each point in space. Its local strength, rather than voltage alone, drives breakdown.
Paschen's law: An empirical relation describing the breakdown voltage of a gas as a function of pressure and electrode-gap distance. It predicts when a gas-filled gap will fail as pressure and spacing change.
Electrical arcing: A sustained electrical discharge through an ionized gas that carries current between separated conductors. An arc can follow breakdown, but breakdown names the transition that creates a conducting path.
Streamer discharge: A rapidly propagating ionized channel formed when an advancing electrical discharge enhances the local electric field at its tip. Streamers can bridge a gas gap and turn localized ionization into a full spark.
Dielectric: An electrical insulator that polarizes in an applied electric field. Breakdown is the failure of a dielectric’s insulating behavior.
Lightning: A natural electrical discharge that transfers charge between clouds, within clouds, or between clouds and the ground. Lightning is a large-scale example of electrical breakdown through air.
Corona discharge: A localized ionization of gas around a conductor where the electric field is strong, without a complete gap-spanning discharge. Corona involves partial gas ionization rather than full breakdown across the insulation gap.
Townsend discharge: A gas discharge in which electron avalanches grow through impact ionization before forming a self-sustaining conducting path. It describes the early avalanche stage of gas breakdown.
Electrical conductivity: A measure of how readily a material carries electric current in response to an electric field. Breakdown sharply raises effective conductivity through the insulating material.

Linked from 14 pages