Deciphering Oxidation-Dominated Abnormal Rheology to Design Performance-Stable Liquid-Metal-Based Nanofluids for Transmission Applications.

Abstract

With global decarbonization urgency for sustainability, enhancing the service stability of liquid metals (LMs) and reducing their oxidation-induced failures are crucial. The oxidation of LMs can adversely affect the fluidity required for hydraulic transmission, thermal management, and other transport scenarios. Given the importance, we have fabricated an LM-based SiC/graphene-Mo nanofluid (LMNF) and compared the rheological behavior to pure LM under an oxidative atmospheric environment. Using an omni-spectrum rotary rheometer and a water bath ultrasonic technique, we quantified a more stable rheological performance in our LMNFs and elucidated how it linked to LMNFs' phase interactions and oxidation. Their temperature-viscosity characteristics are less susceptible to dealloying-accompanied severe oxidation because the nanophase-enabled strong interfacial bonding by SiC, graphene, and Mo gives LMNFs a more viscoelastic solid nature. With these observations, a performance-predicting model, validated through real hydraulic transmission demonstrations, is developed to decipher the relationship among oxidation-influenced rheological performance like viscosity, temperature, and nanophase and guide LMNF design. This model provides a robust framework to fabricate LMNFs for long-term applications with a stable performance.