Revolutionizing Cooling Technology: A Paradigm Shift in Magnetic Refrigeration

In a pioneering advancement, scientists have uncovered a promising Ni (Co)-Mn-Ti Heusler alloy, heralding a sustainable alternative for conventional cooling methods.

Understanding Magnetic Cooling Effect (MCE):

  • Defined as the reversible temperature shift in a magnetic material under an external magnetic field.
  • During the adiabatic process, aligned magnetic moments induce heating, while demagnetization leads to cooling below ambient temperature.
Fig 1. Schematic representation of magnetic refrigeration cycle from the internet

Application in Cooling Technology:

  • Presents an energy-efficient and eco-friendly solution, challenging traditional vapor-cycle refrigeration.

Exploring the New Alloy’s Magnetic Properties:

  • Researchers at S.N. Bose Centre experiment with all-transition metal-based Heusler alloys.
  • Ni35Co15Mn34.5−xCuxTi15.5 (x = 1, 2, and 3) exhibits giant reversible Magnetic Cooling Effect (MCE) and magneto resistance (MR) under 5 T and 7 T magnetic fields.
Fig 2. Four FCC lattices of full-Heusler Ni(Co)-Mn-Ti Heusler alloy

Technical Criteria for Magnetic Materials:

  1. Operational Durability: Must withstand millions of cycles without fatigue.
  2. Thermal Conductivity: High thermal conductivity is crucial.
  3. Magnetic Responsiveness: The material should respond to a 2 T external magnetic field.

Cu-Doping and Structural Transitions:

  • Cu doping strengthens Ni–Ti bond metallic character and weakens Mn–Mn exchange interaction.
  • Induces magnetic transition towards structural transitions, minimizing the distance between them.

Research Outcomes:

  • Ni35Co15Mn34.5−xCuxTi15.5 achieves giant reversible MCE, displaying the highest magnitude in all-d-metal Heusler family.
  • A rare combination – concurrent observation of refrigerant capacity and MR in Heusler alloys.

Unlocking Technological Potential:

  • Synergistic advancements through Cu-doped Heusler alloys may lead to diverse solid-state technological applications.
  • Ongoing efforts aim to harness the alloy’s potential for widespread use in household, industrial, and technological cooling applications.

This research marks a monumental step towards a greener, more efficient cooling future, aligning with global efforts to reduce greenhouse gas emissions.

Source:PIB