Abstract: Amorphous or microcrystalline alloy powder is prepared by the rapid quenching of ultrafine metallic spheroids generated from the molten metal state. The molten metal droplets are formed when an intense electric field (10.sup.5 V/cm) is applied to the surface of liquid metal held in a suitable container. The interactions between the intense electric field and liquid surface tension disrupts the metal surface, resulting in a beam of positively charged droplets. The liquid metal spheres generated by this electrohydrodynamic process are subsequently cooled by radiative heat transfer. Rapid cooling of the droplets may be accomplished by heat transfer to a low pressure gas by free molecular heat conductivity. Quenching rates exceeding 10.sup.6 .degree.K./sec are possible using this technique. Thin film coatings are prepared by electrohydrodynamically spraying a beam of charged droplets against a target (substrate). The target can be electrically controlled to effect the charged particles impact.