Cold-hearth melt-spinning apparatus for providing continuous casting of refractory and reactive alloys

DETAILED DESCRIPTION The cold-hearth melt-spinning apparatus for providing continuous casting of refractory and reactive alloys of the present invention overcomes these and other disadvantages, and contemplates means coupled to the cooled crucible for reducing heat transport from the melt to the confronting wall of the crucible to reduce "freezing" along the melt-to-crucible interface and to reduce power consumption.
The present invention further contemplates means coupled to the cooled crucible for maintaining the orifice at a high temperature sufficient to substantially eliminate "freezing" in and across the orifice and therewith to prevent both orifice restriction and occlusion.
The heat transport reducing means preferably includes a crucible having a surface having a plurality of selectively dimensioned grooves in a selected surface pattern.
The dimensions of the grooves are selected such that the surface tension of the melt prevents it from entering the grooves so that the grooves thereby act to impede heat transport to the cooled crucible and to materially reduce the total melt-to-crucible contact area.
In this manner, melting and superheating is achieved with substantially reduced melt "freezing" and input power requirements.
The high orifice temperature maintaining means preferably includes a refractory nozzle defining an orifice that is friction-fit in an aperture provided therefor in the crucible.
The boundary defined between the confronting walls of the nozzle and crucible defines a high thermal impedance interface.
Heat from the melt is thereby retained by the nozzle producing a nozzle temperature that is sufficient to substantially eliminate melt "freezing" on and across the walls defining the nozzle orifice.
The nozzle is removably replaceable by a clean nozzle between casting without risk of damage to the crucible.
In a preferred embodiment, the cold-hearth melt-spinning apparatus for providing continuous casting of refractory and reactive alloys of the present invention includes a melting chamber, a subjacent spinning chamber, and a processing chamber in communication with the spinning chamber