Conductive ceramic-metal composite body exhibiting positive temperature coefficient behavior

摘要

A conductive composite sintered body exhibiting PTC behavior, including a high electrical resistance matrix and 20 vol %-40 vol % electrically conductive particles dispersed in the matrix to form an electrically conducting three-dimensional network therethrough. The electrically conductive particles are selected from bismuth, gallium, or alloys thereof, and an average distance between the particles, when viewed in an arbitrary cross-section through the sintered body, is no more than 8 times the average particle diameter of the particles. The resistivity of the sintered body is low at temperatures below the melting point of the electrically conductive material and increases substantially at or above the melting point.