Stress analysis of polycrystalline thin films and surface regions by X-ray diffraction

Welzel, U.; Ligot, J.; Lamparter, P.; Vermeulen, A.C.; Mittemeijer, E.J.

doi:10.1107/S0021889804029516

Figure 15
Illustration of the crystallite group method: calculated example. sin² [psi]

plots for the mechanical (lattice) strain for the crystallite group {211}< $[\bar{1}]$ 11> in a copper specimen subjected to a plane biaxial state of stress with $[{\sigma _{11}^{\rm S} }]$ = 100 MPa, $[{\sigma _{22}^{\rm S} }]$ = 200 MPa for three values of [varphi]

(lines). The symbols indicate at which combinations of tilt ( [psi]

) and rotation ( [varphi]

) angles the measurement of the lattice strain by diffraction is possible. As an example, the lattice strain can be measured at sin² [psi]

= 0.25 and [varphi]

= 90°, and at sin² [psi]

= 0.67 and [varphi]

= 0° employing the 220 reflection.