Peculiar Broken Phenomena of Cu Wires Passed by Lightning Current

摘要

When lightning high current flows through a copper wire, the copper wire would be melted or sheared. A straight thin copper wire such as 0.1mm phi is melted due to the specific melting joule integral:(j~2 t)_m in an adiabatic condition. However, it has been recognized that the thick copper wires are not completely melted, but mainly sheared. And peculiar broken processes were observed. Therefore, electro-magnetic mechanical shearing stress, etc. are discussed adding to the ordinary Joule heating. The broken current Ip is smaller than the melted current. The Ip of curved wire is also smaller than that of straight wire and increases with the wire diameter and the curved angle.