Interface strengthening and fracture characteristics of the Ag-based contact materials reinforced with nanoporous SnO2(Cu, CuO) phases

[Display omitted] •Ag-based contact materials reinforced with nanoporous SnO2(Cu, CuO) were successfully prepared.•Fracture toughness of the Ag-SnO2 materials was remarkably improved.•The interfacial bonding strength was markedly enhanced by the loading of Cu and CuO.•The stress concentrations at interface between Ag and SnO2 was decreased.•The porous structure of the SnO2 phase can prevent the crack propagation. The novel Ag-based contact materials reinforced with nanoporous SnO2 were successfully prepared by chemical corrosion combining with powder metallurgy method. The Cu and CuO particles were respectively loaded in the nanoporous SnO2 reinforcements through simply changing corrosion process. The results showed that the stress concentrations in the prepared Ag-SnO2 materials tended to occur inside the porous SnO2 phase rather than interfaces, which inhibited the initiation of cracks. The loading of CuO was beneficial for improving interfacial strength without loss of electrical conductivity. The porous SnO2 reinforcements could shield the crack tip, increasing the fracture toughness of the Ag-SnO2 materials.