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Glass hot embossing is a well-established and cost-effective manufacturing method for glass microstructures. However, the spatial volume affects deformation behaviors in closed mold cavities, which determines the final shape of the embossed glass. To investigate the spatial gas effect on the glass deformation mechanism during hot embossing, we used the focused ion beam (FIB) to fabricate blind micro-hole array structures with different depths as embossing templates. The experimental results demonstrated that the spatial volume of the mold cavity has a great influence on the energy of gas expansion, thus affecting the deformation height of glass microstructures during hot embossing. The deeper the cavity depth, the bigger the surface tension, resulting in larger surface concave deformation. Due to the surface tension of gas expansion, the deformation height of the edge zone is higher than that of the center zone at a higher embossing temperature until the heated glass is completely compressed into the mold cavity. Additionally, at lower embossing temperatures (520 °C), the heated glass has a large deformation resistance and elastic recovery. The more deformation volume escape from the shallower mold cavity because of the spatial effect, thus the deformation height decreases as the cavity depth reduces. The work provides a better understanding of manufacturing glass microstructures in hot embossing. [ABSTRACT FROM AUTHOR]

C f -ZrB 2 -SiC is a new composite material with excellent properties for making the next-generation aerospace component. This material is extremely difficult to removal by mechanical machining, and there is a lack of research on feasible secondary processing methods of this composite at present. Micro-EDM is not limited by material hardness, so it is very suitable for machining this material. In this paper, the Material removal mechanisms and processing characteristics of C f -ZrB 2 -SiC by micro-EDM is analyzed. The removal mechanism of composite materials is explored though the discharge crater morphology, and the single-discharge experiments of each phase materials with different medium and different energies are also carried out as a reference. Electrical discharge milling experiments of C f -ZrB 2 -SiC are performed to explore the medium on processing index, and found that the best surface quality and maximum processing efficiency can be realized in kerosene. An experiment with four factors (pulse width, voltage, peak current, capacitance) and three indexes (surface roughness, MRR, TWR) is designed to analyze the C f -ZrB 2 -SiC process characteristics of micro-EDM and the response surface diagram and second-order regression equation are obtained. Milling the C f -ZrB 2 -SiC by electrical discharge according to the optimal combination of surface roughness parameters deduced above, the as-machined surface is analyzed including the surface morphology by SEM, element content by EDS and the surface phase by XRD. The feasibility and advantages of micro-EDM on machining C f -ZrB 2 -SiC are prove. [ABSTRACT FROM AUTHOR]