The goal of this work is to determine the correlation of the strength of brittleudamorphous nonmetallic materials with the defective surface layers and their physicaludproperties. The defective surface layer of materials for optoelectronic and sensors devicesudconsists of abundant structural near-surface defects, which are displaced under action ofudconstant load and thermal fluctuations, reducing the elasticity of the surface layer.udMicrocreep processes in tested materials can be described by a general equation that isudknown as the logarithmic microcreep equation. The applicability of this equation forudtested optical materials is indicative of the generality of microcreep processes inudcrystalline and amorphous hard materials. For each grade of polished optical glass, audminimal residual defective layer exists. The parameters of this layer are interrelated withudthe mechanical properties of glass, such as microhardness and optical strain coefficient,udand thermophysical properties, such as thermal diffusivity, sintering temperature, andudannealing temperature. The greater are the values of these properties, the less is theudconcentration of disrupted interatomic bonds. Based on the test results, the correspondingudequation, using the parameter E⋅a¹/², for determining the strength of optical silicate glassudand glassceramic has been proposed.
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