Superconducting In Situ/Post In Situ MgB₂ Joints

Area of Science:

• Materials Science
• Superconductivity
• Applied Physics

Background:

• Superconducting joints for in situ MgB₂ wires are crucial for applications like NMR magnets.
• Connecting fully reacted MgB₂ wires requires specialized methods, often involving a second heat treatment with Mg + 2B mixture.
• Existing literature presents varied approaches, including cold pressure and sintering, with ongoing debate on optimal techniques.

Purpose of the Study:

• To investigate and propose an effective thermo-mechanical procedure for creating superconducting joints between in situ reacted MgB₂ wires.
• To address the challenges in joining pre-sintered MgB₂ wires for practical applications.
• To evaluate the performance of the developed joint in terms of critical current.

Main Methods:

• A novel thermo-mechanical procedure was developed for joining in situ reacted MgB₂ wires.
• The process involved utilizing a Mg + 2B flux to facilitate the formation of superconducting joints.
• The critical current (I_c) of the formed joints was measured at 25 K.

Main Results:

• The developed thermo-mechanical procedure successfully formed superconductive joints between in situ reacted MgB₂ wires.
• The critical current of the researched junction reached 50% of the I_c of an individual in situ wire at 25 K.
• The study provides insights into the interfacial requirements for successful joint formation.

Conclusions:

• The proposed thermo-mechanical procedure offers a viable method for creating superconducting joints in MgB₂ wires.
• The achieved critical current demonstrates the potential of this method for practical applications.
• Further research may optimize the process for higher joint performance.