Apparatus for melting metal and method for manufacturing metal

Abstract

An apparatus for melting metals comprises a hearth for melting a metal raw material, a mold for forming an ingot by cooling the molten metal therein, the mold having a bottom, and a base unit for pulling down the ingot and provided at the bottom of the mold. The base unit has a surface provided with a concave portion at an optional location, and the surface of the base unit surrounding the concave portion is inclined toward the concave portion.

1 . An apparatus for melting metals comprising:
 a hearth for melting a metal raw material;   a mold for forming an ingot by cooling the molten metal therein, the mold having a bottom; and   a base unit for pulling down the ingot and provided at the bottom of the mold,   wherein the base unit has a surface provided with a concave portion at an optional location, the concave portion comprises a bottom and a side wall portion that is inclined from the perpendicular direction so as to form an acute angle with the bottom, and the surface of the base unit surrounding the concave portion is inclined toward the concave portion.   
   
   
       2 . The apparatus for melting metals according to  claim 1 ,
 wherein the surface of the base unit inclined toward to the concave portion has an inclination angle of 2 to 10°.   
   
   
       3 . (canceled) 
   
   
       4 . The apparatus for melting metals according to  claim 1 ,
 wherein another concave portion is provided further to the concave portion at the bottom.   
   
   
       5 . The apparatus for melting metals according to  claim 4 ,
 wherein the concave portion provided at the bottom of the concave portion has a bottom surface, and the bottom surface is inclined in any direction with respect to a horizontal surface.   
   
   
       6 . The apparatus for melting metals according to  claim 1 ,
 wherein the base unit for pulling down the ingot has a separable structure so as to allow the ingot formed thereon to be pulled out.   
   
   
       7 . The apparatus for melting metals according to  claim 1 ,
 wherein the base unit comprises a water-cooled copper.   
   
   
       8 . The apparatus for melting metals according to  claim 1 ,
 wherein the apparatus for melting metals comprises one of an electron-beam melting furnace and a plasma-arc melting furnace.   
   
   
       9 . The apparatus for melting metals according to  claim 1 ,
 wherein the metal is selected from the group consisting of titanium, zirconium, and tantalum.   
   
   
       10 . A method for producing metals by using the apparatus for melting metals according to  claim 1 . 
   
   
       11 . The method for producing metals according to  claim 10 ,
 wherein the metal is selected from the group consisting of titanium, zirconium, and tantalum.