Robust ingot for the production of components made of metallic solid glasses

Abstract

A method for production of an ingot of a bulk glass-forming alloy, comprising the steps of: Providing a homogeneous melt of a bulk glass-forming alloy; casting the homogeneous melt into a casting mould, whereby the casting mould does not cool down below the glass-transition temperature of the alloy at the contact surface to the melt for at least 5 seconds; and cooling down the melt below the glass transition temperature of the bulk glass-forming alloy while obtaining the ingot.

1 . A method for production of an ingot of a bulk glass-forming alloy, comprising the steps of:
 a. Providing a homogeneous melt of a bulk glass-forming alloy;   b. casting the homogeneous melt into a casting mould, whereby the casting mould does not cool down below the glass-transition temperature of the alloy at the contact surface to the melt for at least 5 seconds; and   c. cooling down the melt below the glass transition temperature of the bulk glass-forming alloy while obtaining the ingot.   
     
     
         2 . The method according to  claim 1 , whereby the casting mould does not cool down below the glass-transition temperature of the alloy at the contact surface to the melt for at least 10 second. 
     
     
         3 . The method according to  claim 1 , whereby the bulk glass-forming alloy has a critical casting thickness of 5 mm or more. 
     
     
         4 . The method according to  claim 1 , whereby the size of the ingot in the three directions of space is larger than the critical casting thickness. 
     
     
         5 . The method according to  claim 1 , whereby the ingot comprises a crystalline fraction of at least 90%, relative to the weight, as measured by means of DSC. 
     
     
         6 . The method according to  claim 1 , whereby the ingot comprises a crystalline fraction of at least 95%, relative to the weight, as measured by means of DSC. 
     
     
         7 . The method according to  claim 1 , whereby the casting mould is coated with a material selected from the group consisting of boron nitride, Y 2 O 3 , and aluminium oxide. 
     
     
         8 . The method according to  claim 1 , whereby the ratio of the weight of the melt and the weight of the casting mould is 1:7 or less. 
     
     
         9 . The method according to  claim 1 , whereby the temperature of the melt in step a) is at least 20% above the melting temperature, as measured in degrees centigrade. 
     
     
         10 . An ingot of a bulk glass-forming alloy, comprising a critical casting thickness of at least 5 mm, whereby the ingot has an extension in at least three directions of space that is larger than the critical casting thickness, characterised in that the ingot comprises a crystalline fraction of at least 90% by weight, as measured by means of DSC. 
     
     
         11 . A method for production of a three-dimensional component from a bulk metallic glass by means of casting processes, characterised in that an ingot ( 20 ) according to  claim 10  is being melted for the casting process. 
     
     
         12 . The method according to  claim 11 , whereby the melting of the ingot takes no longer than 60 seconds, in particular no longer than 40 seconds.