Study on a new contact material-Ag/SnO/sub 2/-La/sub 2/O/sub 3/-Bi/sub 2/O/sub 3/

Abstract

For this paper, a super-fine compound powder, Ag/SnO/sub 2/+La/sub 2/O/sub 3/+Bi/sub 2/O/sub 3/ has been obtained successfully using the chemical coprecipitation method, and a new contact material, Ag/SnO/sub 2/+La/sub 2/O/sub 3/+Bi/sub 2/O/sub 3/, was produced by the powder metallurgy method. Its properties are as follows: density is 9.75/spl sim/9.93 g/cm/sup 3/, resistivity is 2.31/spl sim/2.551 /spl Omega/cm, and hardness is 880/spl sim/985 MPa. Its microstructure shows that the fine oxides have a uniform distribution in the silver matrix. The results of make-break capacity and temperature rise testing show that the new material has better anti-arc erosion ability and lower temperature rise than that of commonly used Ag/CdO material.