Due to the development of new engineering materials and high-speed cutting, cutting fluid plays an important role in machining. Commonly, the use of cutting fluid can decrease cutting temperature, reduce the friction between tool and workpiece, extend tool life, and improve machining efficiency and surface quality. These effects of cutting fluid were mainly obtained from its basic functions including cooling, lubrication, corrosion protection, and cleaning. According to the review of the researches in cutting fluids applied in metal cutting process, the available researches mainly focused on the application strategies and penetration capability, processing performance, new types of environmentally friendly cutting fluids, and preliminary machined surface quality. This article also suggests that the effect of cutting fluid on machined surface quality and performance will become an important research direction. There is a matching problem between the cutting fluids and the workpiece materials. Further research on effect of cutting fluids on machined surface should include physical and chemical mechanism of the cutting fluid, action mechanism on fresh machined surface during machining process, action mechanism in the period of long-term service, stability of the composition and physical and chemical properties, and evaluation method of the effective use of cutting fluid.

Nanofibrous aerogels constructed solely by ceramic components with temperature-invariant hyperelasticity could have broad technological implications in extreme environments. However, creating such materials has proven to be extremely challenging. Despite the results from laboratory, those aerogels are, unfortunately, still plagued with issues that would retard their further application: inferior structural integrity, failure at large compressive deformation, high production cost, and inability to withstand rigorous working conditions. To tackle these challenges, we report a facile strategy combining the chemical vapor deposition process and layer-by-layer self-assembly to construct hyperelastic SiC nanofibrous aerogels with three-dimensional porous architecture and improved structural integrity. The resultant aerogels outperform their natural counterparts and most state-of-the-art ceramic nanofibrous aerogels in their capability to quickly recover from large compressive deformation (50% strain), function in a wide range of temperatures, from −196 °C to 1100 °C in air, maintain high particle matter removal efficiency of >99.96%, and rapidly absorb various organic solvents and oils with high capacity and robust recoverability. Nanofibrous aerogels constructed by such a versatile method could provide fresh insights into the exploration of multifunctional nanofibrous aerogels for a variety of applications in extreme environments.

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