Materials fabrication method and apparatus

Abstract

A perform ( 28 ) is slip-cast or pressed from a metal compound or a mixture of metal compounds, sintered in air, vacum, or inert gas, and is electrolytically reduced in a bath ( 20 ) of molten salt to form a porous metal or alloy product. The alloy is in the form of a solid, porous sponge. In the bath ( 20 ) the salt is in contact with a reservoir ( 26 ) of molten infiltration material ( 24 ). After completion of the electrolytic reduction the porous product is moved into the infiltration material which fills the pores therein, displacing the salt. The infiltrated product is then solidified for further materials processing.

1 . A method for fabricating a material comprising the steps of; forming a solid, porous sample of a metal or semi-metal or an alloy or intermetallic compound thereof by electrodecomposition in a molten salt; and infiltrating the porous sample with a further material.  
     
     
         2 . The method according to  claim 1 , in which a preform for the electrodecomposition is formed from one or more solid metal or semi-metal compounds or solid solutions, or a mixture or one of these with one or more metals.  
     
     
         3 . The method according to  claim 1 , in which the infiltration step fills pores in the porous sample to fabricate a substantially solid material.  
     
     
         4 . The method according to  claim 1 , in which the infiltration material is a liquid and the infiltration step includes removing the sample from the molten salt and immersing it in the infiltration liquid.  
     
     
         5 . The method according to  claim 4 , in which the sample is cooled on removal from the molten salt, retaining solidified salt within pores in the sample.  
     
     
         6 . The method according to  claim 1 , in which the infiltration material is a liquid and the infiltration step includes transferring the sample directly from the molten salt to the infiltration liquid.  
     
     
         7 . The method according to  claim 6 , in which the infiltration liquid is held in contact with the molten salt.  
     
     
         8 . The method according to  claim 1 , comprising the step of, during infiltration, removing molten salt contained in pores in the sample after electrolysis, for example by pumping or sucking, to assist infiltration by the infiltration material.  
     
     
         9 . The method according to  claim 1 , comprising the step of vibrating the sample to assist infiltration.  
     
     
         10 . The method according to  claim 1 , in which the fabricated material is, or can be further processed to form, a superconductor.  
     
     
         11 . An apparatus for carrying out a method for fabricating a material, wherein said method comprises the steps of; forming a solid, porous sample of a metal or semi-metal or an alloy or intermetallic compound thereof by electro-decomposition in a molten salt; and infiltrating the porous sample with a further material.  
     
     
         12 . A material fabricated using a method comprising the steps of; forming a solid, porous sample of a metal or an alloy or intermetallic compound thereof by electro-decomposition in a molten salt, and infiltrating the porous sample with a further material.  
     
     
         13 . The material according to  claim 12 , comprising an alloy of Nb, Sn and/or Ti.  
     
     
         14 . An apparatus for fabricating a material comprising; a cell in which a molten salt for forming a solid, porous sample of metal, alloy or intermetallic compound by electrodecomposition contacts a liquid material for infiltrating the porous sample; and a transfer mechanism for transferring the porous sample from the salt to the liquid material after the electrodecomposition.