Electric discharge sintering of binary powder mixtures

Conclusions

• 1. Experiments on Cu-Ni composite specimens have provided evidence in support of the hypothesis [7] that electric discharge sintering can induce very rapid alloy formation in powder mixtures (for example, the degree of homogenization attained in a 50% Cu-50% Ni mixture subjected to orthodox isothermal sintering for 4 h at 1050°C requires only 45 sec in the EDS process).

• 2. The key factors in the attainment of a given degree of homogenization in EDS are the integral power consumption and the rate of supply of electrical energy to the powder being sintered.

• 3. It is shown that in the case of a Ni-Mo composite electric discharge sintering, like ordinary isothermal sintering, is accompanied by dissolution of the molybdenum in the nickel.

• 4. The formation of an alloy with a high degree of homogeneity from a mixture of Ni and Mo powders in the EDS process occurs very rapidly (in 1.5–1.75 min), whereas in conventional sintering the same degree of alloy formation is reached only after 2 h at 1500° C.