Abstract
The In-Rotating-Water Spinning Process, in which a molten metal jet is injected into a rotating water bath, can produce rapidly solidified crystalline or amorphous wires with round cross-section. In order to estimate the cooling rate of solidifying wire in the process and to get some nature of the process variables, the water flow around the jet and the microstructure of the obtained wires were examined. The temperature profile of the jet was simulated, and the result was compared with the temperature calculated from the luminance of the jet. Molten Cu85Be11Fe4 (in at%) alloy jet was injected into a water bath of 20 mm depth formed on the inner surface of a drum of 500 mm diameter which rotated at 300 r.p.m.. Separation of water around the jet and around a stainless wire at room temperature which simulates the metal jet was observed by a stroboscopic photograph. The length of the water separation along the stainless wire increased with decreasing wettability of the wire by water. The heat transfer in the region of the water separation from the jet seemed to be forced convectional film boiling. The dendrite arm spacing of the Cu-Be-Fe wire increased with increasing water temperature and was not so much affected by the ejection temperature. The cooling rates of the jet during solidification was estimated to be about 105 K/s from the dendrite arm spacing and this was supported by the simulation. It was found that the temperature profile of the metal jet could be estimated from the luminance of the jet which was measured from the photographic paper. Epstein and Hauser’s equation for the forced convectional film boiling heat transfer would be applicable to the heat transfer in this spinning process.
