Cu Multiply Twinned Particle Precipitationin Low-Temperature Fired Ni-Zn-Cu Ferrite

Abstract

Cu metal precipitates and truncated Cu metal multiply twinned particles (MTPs) were observed in low-temperature fired ferrite with a small excess of Ni-Zn-Cu chemical composition. The Cu metal precipitates suggest the existence of Cu solid solution and accelerated grain growth during the sintering accompanied with the formation of defect structures, such as oxygen vacancies in the ferrite spinel structure. The defect structure compensation during the cooling process after sintering results in Cu metal precipitation at the multiple grain junction.