New Stacked Porous NiTi Structure Achieves High Cooling Power

A novel stamping and stacking method produces fatigue-resistant NiTi structures for elastocaloric cooling, enhancing heat transfer and reducing costs.

Researchers have developed a new method for producing porous, fatigue-resistant shape memory alloy (SMA) structures for elastocaloric cooling (eC). The stamping and stacking (S-S) technique involves creating honeycomb-like chips from nitinol (NiTi) thin sheets, which are then assembled into a tubular structure. This design increases the heat exchange surface while preventing common failures such as buckling and splitting. The resulting structure can withstand over 10^8 compression cycles and delivers a specific cooling power of 3850 watts per kilogram. Additionally, the S-S method reduces fabrication costs by an order of magnitude compared to existing techniques, facilitating the mass production of eC refrigerant structures for commercial use. science.org