Study on Ag-92SnO2In2O3electrical contacts fabricated by In-Situoxidation process

Abstract:

Intermediate Ag-60SnO₂In₂O₃powders were synthesized by in-situ oxidation and traditional oxidation process with Ag-65SnIn-8 melting atomization powder as raw material, Ag-92SnO₂In₂O₃materials were prepared by mixing-isostatic press and sintering-Hot extrusion technology, and then Ag-92SnO₂In₂O₃/Cu/Fe contacts were fabricated by the solid phase bonding process.Compared with that synthesized by traditional oxidation process, Ag-92SnO₂In₂O₃/Cu/Fe contacts fabricated with in-situ oxidated Ag-60SnO₂In₂O₃ as reinforcing phase had lower electrical resistivity ( 2.1 μΩ.cm) and proper hardness(85~110HV). By installing the contacts in motor loaded-thermal protection circuit ( power factor 0.7, 380V, 65A), the results of eletrical life testing showed that Ag-92SnO₂In₂O₃ electrical contacts fabricated by In-Situ oxidation process had higher operations(＞5000 times) which was met the requirements and could substitute for AgCdO/Cu/Fe electrical contacts.

Key words:In-situ oxidation process; SnO₂In₂O₃; silver based electrical contact material; electrical resistivity; electrical life testing