I-Corps: High efficiency multi-material heat sink/storage by additive manufacturing

The broader impact/commercial potential of this I-Corps project is the development of an additive manufacturing process to produce solid-state heat management systems using shape memory alloys (SMAs). SMAs benefits from a solid-solid phase transformation, which is of interest in many applications of heat sink/storage. However, there are challenges in processing of SMAs such as nickel titanium (NiTi) using conventional methods, which limits its design to simple geometries. The proposed technology overcomes these challenges by fabrication of SMAs through additive manufacturing methods. Heat management systems using NiTi may be additively manufactured using 3D printing technology. This technology may have a wide range of applications including heat sink/storage for satellites, telecommunication antennas, and consumer electronics. There is a growing need to develop better solid-state heat management systems driven by the need for safer and more environmentally friendly systems. This I-Corps project is based on the development of an additive manufacturing method to fabricate shape memory alloys into complex geometries. Shape memory alloys such as nickel titanium (NiTi) offer solid-solid phase change, which reduces the risk of leakage observed with other phase change materials. In addition, NiTi as a phase change material with high volumetric latent heat as well as excellent corrosion resistance has been reported to improve the efficiency for thermal storage systems. The proposed technology couples phase changing NiTi material with a high thermal conductivity material such as copper to produce energy storage and conversion systems. It has been demonstrated that using a sandwich of NiTi/Copper can increase the time to reach the critical temperature when compared to a copper heat sink alone. This result indicates that this may be used in a wide range of applications including heat sink/storage for satellites, telecommunication antennas, and overshoot controllers. Moreover, the reversible solid-solid martensite transformation eliminates the risks of leakage and reduces the cost of maintenance of these applications. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.