A research team from the Korea Institute of Materials Science (KIMS) has made significant strides in refrigeration technology by developing Korea’s first full-cycle magnetic cooling system. Led by Dr. Jong-Woo Kim and Dr. Da-Seul Shin, this pioneering technology aims to replace conventional gas-based refrigeration methods, addressing pressing environmental concerns linked to greenhouse gas emissions.
The innovative magnetic cooling technology operates without gas refrigerants, utilizing the magnetocaloric effect, which allows temperature changes in a refrigerant material when an external magnetic field is applied. This approach offers a promising alternative to traditional refrigeration systems, but challenges have hindered its commercialization. High manufacturing costs of magnetocaloric materials and reliance on rare-earth elements have complicated production, making it difficult to remain price competitive in the market.
Despite these challenges, the KIMS team has successfully synthesized various magnetocaloric materials, including lanthanum (La)-based and manganese (Mn)-based alloys. They employed advanced fabrication techniques such as hot rolling, cold drawing, and micro-channel machining to create efficient sheet and fine-wire specimens. Notably, the researchers produced large-area La-based thin sheets, measuring only 0.5 mm thick, and Gd-based fine wires with a diameter of 1.0 mm, demonstrating exceptional performance at the component level.
To enhance cooling efficiency, the team also improved non-rare-earth Mn-based materials by controlling thermal hysteresis and adjusting magnetic anisotropy. A significant breakthrough in their research was the development of Korea’s first measurement system, capable of directly monitoring adiabatic temperature changes in magnetic cooling materials. This advancement allows for the quantitative verification of property differences and supports the optimization of materials and components for magnetic cooling applications.
As global regulations on refrigerants tighten, particularly under the Kigali Amendment to the Montreal Protocol, the urgency for eco-friendly refrigeration technologies grows. By 2030, the production and use of major gas refrigerants, including HFCs, HCFCs, and R22, will face a complete ban. The trend is further reinforced by studies in technologically advanced nations, such as Germany, where magnetic cooling systems have exhibited coefficients of performance (COP) exceeding those of conventional methods.
In light of increasing global decarbonization efforts, the KIMS research team is committed to enhancing its competitiveness in magnetic cooling technologies. They aim to achieve high-impact publications and secure critical patents in this evolving field. “Once commercialized, this technology will overcome the limitations of conventional gas-based cooling systems and provide an eco-friendly and stable cooling solution,” stated Dr. Jong-Woo Kim.
His colleague, Dr. Da-Seul Shin, emphasized the importance of this research project, noting that it aims to advance magnetocaloric technology and establish a domestic industrial infrastructure. The team’s research was funded by the Basic Research Program of KIMS and the Creative Convergence Research Program of the National Research Council of Science and Technology (NST). The findings were published in the esteemed journal Rare Metals in May 2025, with Ph.D. candidate Sun-Young Yang as the lead author.
Additionally, the team has registered a domestic patent regarding the magnetic cooling evaluation system and has filed a corresponding application in the United States. With these advancements, the KIMS team is poised to make a significant impact in the global market for eco-friendly cooling technologies.
