The mechanical properties of lithium tetraborate (100), (011) and (112) faces

The mechanical properties of lithium tetraborate (LTB) were studied using micro- and nanoindentation on (100), (011) and (112) oriented plates. The lowest values of the hardness obtained for the LTB (100) face are caused by relatively easy cleavage parallel to the {100} planes. The hardness values decrease at the maximal load increasing for the LTB faces studied, however the indentation size effect is less pronounced for the LTB (011) face. The residual stresses of the indent area were detected using a micro-Raman spectroscopy of indents. It was found that the LTB does not exhibit irreversible phase transitions at an applied load range up to 113–130 mN.