Device and method for the densification of filaments in a long superconductive wire

A device for high pressure densification of superconducting wire from compacted superconductor material or superconductor precursor powder particles, the device comprising:

• a first hard metal anvil;
• a second hard metal anvil disposed adjacent to said first hard metal anvil;
• a third hard metal anvil disposed adjacent to said second hard metal anvil and opposite to said first hard metal anvil;
• a fourth hard metal anvil disposed adjacent to said third hard metal anvil and said first hard metal anvil and opposite to said second hard metal anvil;
• a first pressure block in which said first anvil seats;
• and
• a first pressure device cooperating with said first pressure block to urge said first pressure block and said first anvil towards said third anvil,
• wherein said first anvil is a free moving anvil having clearances of at least 0.01 mm up to 0.2 mm with respect to said second and said fourth anvils, so that no wall friction occurs among said first, second, third and fourth anvils, said first, second third and fourth anvils having a total length parallel to the superconducting wire.