Abstract
The fine powders were prepared by the explosion of iron, nickel, copper and niobium wires in air or under an argon gas atmosphere, which resulted from electric discharge. Concerning the collected powders, the properties and metal contents were examined.
The average particle. sizes which were measured by the centrifugal sedimentation method were less than 1.0μm in all powders, and decreased to 0.3-0.5μm with an increase in the energy ratio. They also did not depend on the kind of wire and atmosphere. The crystallite sizes of the oxide powders made from iron and nickel wires in air decreased with an increase in the energy ratio, and became to constant value, 40-50nm at higher energy ratio. The products obtained in air were mainly oxides, and ones obtained under an argon gas atmosphere were metal and oxides. Reducing the energy ratio led to increasing in the metal contents in the powders, which prepared by the explosion of nickel, copper and niobium wires under an argon gas atmosphere, to 40, 100 and 30%, respectively.
