Electrical and mechanical lives of Ag/C and Ag/WC/C Contacts

Author

Chi Leung ; Harman, Doug ; Doublet, L. ; Bourda, C. ; YuSheng Cui ; Lifu Hu

Author_Institution

Electrotechnics Div., Metalor Technol. Americas, Export, PA, USA

fYear

2012

fDate

14-17 May 2012

Firstpage

233

Lastpage

239

Abstract

Several Ag/C and Ag/WC/C contact materials used as stationary contacts in MCCB (molded case circuit breakers) are compared for electrical and mechanical properties. The mechanical lives of the MCCB can be limited by the stationary contact chipping due to the impact by the much harder moving contacts of Ag/W and Ag/WC. Transverse Rupture Strengths are therefore measured by a 3 point bending test, and impact lives on a model switch designed to evaluate material cracking and chipping. The test results are discussed to illustrate the optimization of metallurgical and electrical properties.

Keywords

bending; carbon; circuit breakers; cracks; electrical contacts; fracture toughness testing; silver; switches; tungsten compounds; Ag-WC-C; MCCB; contact materials; electrical lives; electrical properties; material cracking evaluation; mechanical lives; mechanical properties; metallurgical optimization; model switch; molded case circuit breakers; moving contacts; stationary contact chipping evaluation; three point bending test; transverse rupture strengths; ASTM -B528; Ag-WC-C; AgC; AgWC; arc erosion; arc mobility; electric contact; transver rupture strength;

fLanguage

English

Publisher

iet

Conference_Titel

Electrical Contacts (ICEC 2012), 26th International Conference on

Conference_Location

Beijing

Electronic_ISBN

978-1-84919-508-9

Type

conf

DOI

10.1049/cp.2012.0653

Filename

6301898