Size effects of the strength and elastic properties of individual phases and interphase boundaries of polycrystalline materials

Size effects of hardness are studied and numeric values of Young’s modulus E, hardness H, and fracture toughness coefficient K_c of individual phases and interphase boundaries of polycrystalline samples of ferruginous quartzite are determined by means of micro- and nanoindentation methods. It is found that the interphase boundary of magnetite and hematite is the one most strengthened, while the boundary of the hematite and quartz is the one least durable.