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The surface properties of metals and alloys are usually altered by spray coating techniques for better performance in extreme conditions such as: erosive-corrosive and wear applications. In this study a wear and corrosion resistant coating composition of 75% Cr 3 C 2 -25% (Ni-20%Cr) was selected for cold spraying on N06601superalloy which can sustain in high-temperature applications. Microstructure properties of cold sprayed coating depend upon the composition and mechanical-physical properties of both coating and substrate materials, and cold spraying of brittle carbide-based materials is still a challenge for researchers. Various spray parameters were adjusted in this study to produce a 289 µm thick, smooth and dense (porosity less than 1) cold sprayed coating on 601-alloy with high hardness of 866 HV. For mitigating the erosion-corrosion phenomenon the coating microstructure is as important as its composition. This coating structure is suitable for further testing in high temperature and extreme corrosive conditions.

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Polymer single crystal (SC) is a key building block of semicrystalline polymers. However, direct experimental measurement of freestanding mono‐lamella polymer SC has not been demonstrated. This is, in large part, due to the difficulties associated with manipulating freestanding individual mono‐lamella SC because of its extremely low rigidity and low robustness. Here, we demonstrate a new strategy to successfully suspend and test a polymer SC by using a 2D material as backing. In particular, mono‐lamella polyethylene (PE) SC is stacked on monolayer MoSe2, and the hybrid stacks can be suspended over microholes. Nanoindentation is used to probe the suspended PE‐SC/MoSe2 stacks and MoSe2 monolayers. The results suggest the first experimentally‐measured in‐plane moduli of PE‐SC and 2D MoSe2 as 32 ± 3 and 237 ± 15 GPa, respectively. Such a stacked unit represents an ultrathin structure of polymer‐ceramic laminate and the idea can be applied to other laminated composite systems. Therefore, this research will pave the way to accurately measure the mechanical properties of polymer SCs and their composites, as well as provide a key insight on designing composite structures.