Zinc sulfide (ZnS) is a widely used material in far-infrared and near-infrared imaging systems due to its exceptional optical transmittance properties. Through a hot isostatic compression process, during manufacturing, ZnS undergoes crystal structure modifications, resulting in increased transmittance across the visible and infrared spectra. However, ZnS exhibits low fracture toughness and irregular crystal orientations, making it prone to brittle fracture during the conventional cutting processes. Such brittleness often leads to surface defects that scatter light, diminishing optical transmittance. Therefore, understanding the conditions conducive to ductile processing is critical and necessitates a thorough brittle fracture analysis. This study introduces a novel quantitative analysis method to determine the occurrence of ductile processing and brittle fracture in ZnS materials after the turning process. To validate the efficacy of this approach, experimental machining was conducted through diamond turning and magnetorheological fluid polishing processes. Subsequently, a comprehensive quantitative assessment of brittle fracture was performed. Additionally, the relationship between brittle fracture and optical transmittance was explored using the proposed analysis method.

In this study, we developed a convenient method to achieve superoleophobic surfaces on zinc substrates by using anodization and self-assembled monolayer coating, and to facilitate the fabrication of superoleophobic surfaces having reentrant structures, even for lower surface tension liquids than 30 mN/m- including hexadecane (γ = 27.5 mN/m). The liquid repellency of the structured surface was validated through observable experimental results; contact angle measurement. The optimal anodizing condition was determined as a critical parameter in building the superoleophobicity. The re-entrant had nanowire/microball structures formed by anodization with a high voltage. Under an optimized morphology by re-entrant structures with fluorination treatment, the contact angle over 150o is achieved, even for hexadecane.