Method and apparatus for producing amorphous alloy sheet, and amorphous alloy sheet produced using the same

Abstract

The present invention provides a method for producing a bulk amorphous alloy sheet with high quality at low production cost, by which an alloy melt can be directly transformed into a sheet form without using other additional processes. The method comprises preparing a melt containing alloy components; feeding the melt into a gap defined between two rolls, which rotate in opposite direction to each other, and each of which is provided with heat exchange means; and cooling the melt at a cooling rate higher than the critical cooling rate for transformation of the melt into an amorphous solid phase, when the melt passes through the gap defined between the two rolls. The present invention also provides an apparatus for producing a bulk amorphous alloy sheet with high quality at low production cost, and a bulk amorphous alloy sheet.

1 . A method for producing a bulk amorphous alloy sheet, the method comprising: 
 preparing a melt containing alloy components;    feeding the melt directly into a gap defined between two rolls, which rotate in opposite direction to each other, and each of which is provided with heat exchange means; and    cooling the melt at a cooling rate higher than the critical cooling rate for transformation of the melt into an amorphous solid phase, when the melt passes through the gap defined between the two rolls,    wherein the rotation rate of the two rolls is in the range of 1 to 10 cm/sec, and the gap between the two rolls is in the range of 0.5 to 20 mm.    
     
     
         2 . The method according to  claim 1 , wherein the step of preparing the melt is carried out in an inert atmosphere.  
     
     
         3 . The method according to  claim 1 , wherein the heat exchange means is a circuit for flow of a cooling fluid.  
     
     
         4 . The method according to  claim 3 , wherein the cooling fluid is cooling water or cooling oil.  
     
     
         5 . The method according to  claim 1 , wherein the two rolls are made of a copper-based alloy containing material.  
     
     
         6 . The method according to  claim 1 , wherein the temperature of the melt to be fed into the gap defined between the two rolls is in the range of 500 to 1,500° C., the surface temperature of the two rolls is in the range of 15 to 30° C.  
     
     
         7 . The method according to  claim 1 , wherein the two rolls are arranged in such a manner that an angle defined by the horizontal and a straight line connecting the respective rotation centers of the two rolls, is in the range of 0 to 90 degrees.  
     
     
         8 . A bulk amorphous alloy sheet prepared by the method according to  claim 1 .  
     
     
         9 . The bulk amorphous alloy sheet according to claims  8 , which has a thickness of 0.5 to 20 mm.