Charging and discharging phenomena in oxides, electrical and mechanical applications

Research was conducted to investigate (1) the origin of the correlation which exists between the charging of insulators and their properties (breakdown, fracture toughness, wear, etc.); (2) the origin of the analogy which exists between electric properties and mechanical properties of insulators; and (3) the origin of electron and photoemissions which occur prior to or at the instant of the catastrophe (breakdown, fracture). A theoretical approach to charging and discharging phenomena has made it possible to develop an experimental method giving characteristic dielectric parameters: permittivity, distribution of defects, and energy which can be dissipated inside the insulator without initiating a catastrophe. This method was used to correlate these parameters with the breakdown voltage of oxides and of polymers, and with mechanical properties of ceramics. New high performance materials were prepared