PSI - Issue 80

Miroslav Hrstka et al. / Procedia Structural Integrity 80 (2026) 471–492 M. Hrstka et al./ Structural Integrity Procedia 00 (2025) 000 – 000

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Fig.8. Domain switching zone for an interface crack loaded by σ 2 appl = 20 MPa for the initial poling direction 9 0° with respect to the interface. For comparison, the switching zone is displayed both for temperature change ΔT = –160 °C and ΔT = 0 °C ; on the right-hand side the detailed view is shown. To understand this peculiar behavior, it is necessary to analyze individual terms in the criterion (42). First of all, notice that for α 1 =0 ° the change in spontaneous strain components are Δε 11 < 0, Δε 22 > 0 and the change in spontaneous polarization components Δ P 1 < 0, Δ P 2 >0 or < 0, the latter depending on the orientation of the switching angle. When the thermal misfit strains are included, the stress component σ 11 >0 for 0 < θ < π /2, thus making the contribution to the switching criterion negative in this range, and σ 11 < 0 for π /2 < θ < π , thus making the contribution to the switching

Fig. 9. Comparison of stress components σ 11 , σ 22 in case of the initial poling direction 0° for thermal misfit strains included ( ΔT = –160 °C ) and thermal misfit strains not included ( ΔT = 0 °C )

Fig. 10. Comparison of electric field components in case of the initial poling direction 0° for thermal misfit strains included ( ΔT = –160 °C ) and thermal misfit strains not included ( ΔT = 0 °C )