# name
Atomic force microscopy study of nanoindentation deformation and indentation size effect in MgO crystals

# metadata.dc.description.abstract[].value
The dependences of various nanoindentation parameters, such as depth of penetration
d, indentation diameter a, deformation zone radius R, and height h of hills piled up
around indents, on applied load were investigated for the initial (unrecovered) stage of
indentation of the (100) cleavage faces of MgO crystals by square pyramidal Si tips
for loads up to 10 mN using atomic force microscopy. The experimental data are
analyzed using theories of elastic and plastic deformation. The results revealed that
(i) a, R, and h linearly increase with d; (ii) the development of indentation size and
deformation zone and the formation of hills are two different processes; (iii) the load
dependence of nanohardness shows the normal indentation size effect (i.e., the
hardness increases with a decrease in load); and (iv) there is an absence of plastic
deformation involving the formation of slip lines around the indentations. It is found
that Johnson’s cavity model of elastic–plastic boundary satisfactorily explains the
experimental data. The formation of hills around indentations is also consistent with a
new model (i.e., indentation crater model) based on the concept of piling up of
material of indentation cavity as hills...

# metadata.dc.source[].value
Articles publicats en revistes (Ciència dels Materials i Química Física)

# metadata.dc.title[].value
Atomic force microscopy study of nanoindentation deformation and indentation size effect in MgO crystals