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Electrical discharge machining (EDM) method is an innovative method for the fabrication of structured array surfaces on binderless tungsten carbide (WC) which is a typical embossing mold material, compared to traditional machining methods. To improve the convenience of electrode replacement and the fabrication efficiency of the structured array, a novel self‐assembly ball electrode is innovatively developed. The feasibility of machining binderless WC with a self‐assembly ball electrode was studied and its effect on profile deviation analyzed. Furthermore, the discharge condition's effect on surface roughness, material removal rate (MRR), and tool wear ratio (TWR) was investigated. The microstructure, phase structure, and element distribution of binderless WC caused by EDM were characterized by Raman spectroscopy, scanning electron microscopy, and energy dispersive x‐ray spectroscopy. The results indicated that the maximum profile deviation of the different random structured arrays was about 3.7 μm. The surface roughness of all structured arrays was below 1 μm. The maximum TWR was about 0.008 mm3/min. Besides, the binderless WC surface after EDM presented strong D and G carbon peaks, which means the precipitation and transformation of the WC phase during the discharge process. Finally, different kinds of self‐assembly ball electrodes are developed and used to fabricate the lens array structures on binderless WC. The fast fabrication of the micro‐lens array surfaces in different arrangements sheds some light on the design and manufacturing of other functional structured surfaces. [ABSTRACT FROM AUTHOR]

Glass‐embossing technology has attracted great attention due to its promise of low‐cost and environmentally conscious fabrication of well‐defined and controllable surfaces and nanostructured devices. The embossed surface quality of glass structures is a very important index for optics. However, the evolutions of nanosurfaces and their microcontact mechanism during glass‐embossing process have not been deeply and comprehensively investigated. Here, we studied the surface morphology evolution of optical glass under different processing conditions using a tungsten carbide surface plate with nanoscale roughness as the mold. The light transmittances of different embossed glasses were detected by an ultraviolet spectrophotometer. The flow deformation and microcontact mechanism of glass‐supercooled liquids were revealed during glass‐embossing process. The result showed that the rough optical glass can successfully replicate the nanoscale smoothness of the tungsten carbide template without grinding or polishing. On the basis of the previous study, the glass‐surfaced structures from nanoscale to macroscale are fabricated. This work provides better understanding for the evolution of nanosurfaces and the fabrication of nanostructured optics during glass‐embossing process. [ABSTRACT FROM AUTHOR]

The aim of this study was to thoroughly investigate the effect of temperature on the deformation behavior and optical performance of moulded glass in a nonuniform temperature field. Experiments and numerical simulations were used to analyze how different temperature gradients distributed across a glass cylinder affected the deformation behavior of the moulded glass. Additionally, the imaging quality of the moulded glass lens was detected using the optical measurement system. The results show that the overall shape of the moulded glass cylinder was mainly determined by the value of the temperature gradient. The larger temperature gradient led to smaller deformation angle θ in the moulded glass cylinder. Temperature difference inside the glass dominantly affected the deformation behavior and surface morphology in the nonuniform temperature field, which greatly determines the imaging quality of glass lenses. The results of this study are significant for glass lens fabrication. [ABSTRACT FROM AUTHOR]