Activated and/or liqid phase sintering of mechanically milled naocrystalline powers

摘要

In the present work, we examined activated sintering and liquid phase sintering of mechanically milled metastable powders in pure Ni, Ni_(50)Cu_(50) and Mo_(33)Si_(67). Activating or binder metals such as B, Al, Ag and si were added to the highly ball-milled powders prior to sintering or hot-pressing. Full densification was achieved by a proper selection of additive elements and their content, while retaining naocrystalaline structure. Grain growth was retarded by applying pressure in Mo_(33)Si_(67). The results showed that activated sintering and liquid phase sintring can be used as an effective method for producing dense nanocrystalline alloys made from mechanically milled metastable powders, as well as for producing an exotic microstructure consisting of nanocrystalline/interpenetrating phases.