Mechanical Properties and Microstructure of Zinc Oxide Varistor Ceramics

Abstract:

Article Preview

ZnO varistors are nonlinear resistors used as surge arresters in power transmission and distribution for the protection of electronic devices. Electrical characteristics of these materials have been extensively studied, but their mechanical behavior is not completely understood. It has been suggested that the breakdown of ZnO varistors is related to microstructure heterogeneities and processing defects. These defects are the same that usually control the mechanical strength of ceramic materials. In this work, mechanical properties (flexural strength, fracture toughness, elastic constants, and hardness) of five commercial blocks of ZnO varistors (class I) from different producers were measured and correlated to their microstructure. Pore fraction and size significantly affected the flexural strength.

Info:

Periodical:

Materials Science Forum (Volumes 530-531)

Edited by:

Lucio Salgado and Francisco Ambrozio Filho

Pages:

408-413

DOI:

10.4028/www.scientific.net/MSF.530-531.408

Citation:

H.N. Yoshimura et al., "Mechanical Properties and Microstructure of Zinc Oxide Varistor Ceramics", Materials Science Forum, Vols. 530-531, pp. 408-413, 2006

Online since:

November 2006

Export:

Price:

$35.00

In order to see related information, you need to Login.

In order to see related information, you need to Login.