SBIR Phase I: Shape memory alloys with large latent heat low fatigue for solid-state refrigeration

这个小企业创新研究一期项目的重点是开发具有长疲劳寿命的热弹性材料，适用于制冷和冷却应用。热弹性冷却（TC）是一种利用形状记忆合金（SMA）在应力诱导相变过程中产生和吸收的潜热进行冷却的新技术。热弹性冷却过程的效率很高，其性能系数（COP）估计为11.8，是最先进的蒸汽压缩技术的两倍。然而，这项技术在目前的初步形式中存在缺陷；这包括相对较低的潜热（~12 kJ/kg）和有限的疲劳寿命。该项目的目标是开发一种用于TC应用的新型SMA材料，该材料具有长疲劳寿命和小热滞后的特点。新方法，如厚膜合成和微压痕，将用于制备样品。然后根据迟滞、潜热和应力-应变关系对所得材料进行表征。该项目的广泛影响和商业潜力是巨大的，最终产品有可能在各种住宅和商业冷却和制冷应用中取代蒸汽压缩技术。如果成功商业化，这项技术可以在2030年将美国每年的一次电力消耗减少3.73四分之一。由于热弹性冷却方法完全消除了对一类高全球变暖潜能值（GWP）温室气体的需求，即氢氯氟烃（HCFCs）和氢氟碳化物（hfc），因此总二氧化碳节约量可高达3.68亿吨。基于TC方法的产品的成功商业化和部署可以创造数百个高质量的国内就业机会，其中大多数来自制造业。

This Small Business Innovation Research Phase I project focuses on developing thermoelastic materials with long fatigue life, suitable for refrigeration and cooling applications. Thermoelastic cooling (TC) is a new technology based on the latent heat generated and absorbed during the stress-induced phase transformation in a shape memory alloy (SMA). The efficiency of the thermoelastic cooling process is high, with a coefficient of performance (COP) estimated at 11.8, which is double that of state-of-the-art vapor compression technology. This technology, however, has drawbacks in its current preliminary form; these include a relatively low latent heat (~12 kJ/kg) and a limited fatigue life. The objective of this project will be to develop a new SMA material for TC applications, which features long fatigue life and small thermal hysteresis. Novel methods, such as thick-film synthesis and micro-indentation, will be used to prepare samples. The resulting materials will then be characterized based on hysteresis, latent heat, and stress-strain relationships.The broader impact/commercial potential of this project is huge, with the resulting products having the potential to displace vapor compression technology in a variety of residential and commercial cooling and refrigeration applications. If successfully commercialized, this technology could reduce U.S. annual primary electricity consumption by up to 3.73 quads in 2030. Since the thermoelastic cooling method completely eliminates the need for an entire class of high global warming potential (GWP) greenhouse gases, namely hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs), the total CO2 savings could be as high as 368 million metric tons. A successful commercialization and deployment of products based on the TC method could create hundreds of quality domestic jobs, with most coming in the manufacturing sector.