Fabrication and properties of low oxygen grade Al_2O_3 dispersion strengthened copper alloy

The low oxygen grade Al 2O 3 dispersion strengthened copper alloy without hydrogen fired expansion was fabricated by the technique of vacuum hot press and hot extrusion. The mechanical and electrical properties measurements and microstructures observation on as hot extruded, as cold drawn and as annealed Cu Al 2O 3 alloy were conducted. The results show that the addition of a suitable amount of boron in the alloy can lower the residual free oxygen content and then inhibit the hydrogen fired expansion. The density, σ b, σ 0.2 , hardness, δ and electrical conductivity of the alloy reach 8.86 g/cm 3(relative density of 99.6%), 340 MPa, 250 MPa, HB95, 24% and 93%(IACS) respectively after hot extruded with the extrusion ratio of 30∶1. Its properties have no change after annealed at 900 ℃ for 1 h. Its strength increases after cold drawing, while its ductility and electrical conductivity drop gradually. Various properties of the cold drawn alloy can recover to those of as extruded after annealed at 900 ℃ for 1 h without the occurrence of recrystallization.