Study of microhardness of lithium-borate glasses

The article investigates the microhardness of some lithium-borate glasses in the B2O3-Li2O system under various loading conditions. The experiments included microhardness measurements using a Vickers pyramidal indenter under loads of 0.01 N and 0.025 N. Hardness indentation was performed automatically with a hold time under load from 1 to 5 seconds with a step of 1 second. The results showed that with an increase in the hold time and load, the microindentation depth increases, while the microhardness values decrease. With an increase in the Li2O content the indentation depth decreases, which indicates an increase in the microhardness of the material. Introduction of lithium oxide strengthens the glass structure and increases its resistance to deformation. We have found a linear dependence of the indentation depth on the hold time for all the studied glass compositions, which indicates the predictability of the material behavior under these conditions.