Preparation of Free γ-Iron Particles Quenched to Room Temperature

A smoke of α-iron particles was produced by evaporation and subsequent condensation of iron in an atmosphere of argon. The smoke thus produced was introduced into a furnace at about 1000°C, where the γ-phase was stable. It was then blown against a surface cooled by liquid nitrogen. The smoke particles deposited there were examined at room temperature by electron diffraction and electron microscopy. It was proved that about 10% of the deposited particles (diameter, 500 Å ) were of the γ-phase.