Arya Bhatta Journal of Mathematics and Informatics

Hardness is a measure of a material's resistance to permanent deformation. High-hardness materials are essential in the design and fabrication of tools, engine parts, and dies. The relationship between bond ionicity and hardness is also significant for ceramics and glasses. The widely used Mohs scale helps create scratch resistant glass and heat-resistant materials for modern photovoltaic modules. Limited research has focused on linking hardness to chemical properties like bond ionicity. This study successfully develops an empirical equation that connects bond ionicity to a material's hardness. By extending the concept to atomic stiffness, ionic stiffness, and bond hardness based on electron-holding energy per unit volume, we find that isolated atomic or ionic stiffness is not directly related to material hardness. Instead, material hardness is closely associated with bond hardness, which is defined by the electron-holding energy of the chemical bonds within a material. This model provides a framework for evaluating material hardness based on bond hardness, offering a more profound insight into material hardness at the atomic scale and facilitating the discovery of new super hard materials.