Study on the behavior of silver rare earth oxide contact material

In this paper, a new silver rare earth oxide contact material was produced by powder metallurgy methods. Its properties are as follows: the density is 9.71/spl sim/9.96 g/cm/sup 3/; the hardness (HB) is 760/spl sim/970 MPa; and the resistivity is 2.25/spl sim/2.38 /spl mu//spl Omega/cm. The microstructure of Ag/La/sub 2/O/sub 3/(12) was analyzed by SEM and EDS. The results were that rare earth oxide La/sub 2/O/sub 3/ shows two shapes, i.e. uniform global and abnormality distributions in the Ag matrix. La/sub 2/O/sub 3/ shows a fine spherical shape in the melted area of Ag after laser action which has been used to simulate the effects of an electrical arc. The fine particles contribute to the lower splash erosion of Ag. Compared with the main physical and mechanical properties of Ag-SnO/sub 2/(12) and Ag/CdO(12), the properties of three contact materials are close, hence Ag/La/sub 2/O/sub 3/(12) may become a new contact material which can be substituted for Ag/CdO(12).