Stress on the atomic level perfect crystals are

  • No School
  • AA 1
  • 51

This preview shows page 44 - 51 out of 51 pages.

STRESS ON THE ATOMIC LEVEL Perfect crystals are structures without stress Stress is generated by External forces Deformation of atomic structure and dislocations Stoichiometric errors For atomistic structures: Stress results from the superposition of all forces in between all atoms Stress is for each individual structure Only a structure which represents the solid realistically results in representative stress distribution 44 Rultile stucture PSE Garmisch-Partenkirchen 2016 Marco Jupé LZH
Image of page 44
TIO2 – STRUCTURE PROPERTIES 0.1 eV 10 eV 45 PSE Garmisch-Partenkirchen 2016 Marco Jupé LZH Modelled TiO 2 structure; 56 nm 2 base area; 10 5 deposited atoms; layer thickness ~ 20 nm
Image of page 45
STRESS – Al 2 O 3 2.25 2.50 2.75 3.00 3.25 3.50 3.75 -1.6 -1.4 -1.2 -1.0 -0.8 -0.6 -0.4 -0.2 0.0 0.2 PMA162004 Stress S xx [GPa] Density [g/cm 3 ] -1.6 -1.4 -1.2 -1.0 -0.8 -0.6 -0.4 -0.2 0.0 0.2 Stress S yy [GPa] Growth in z-direction Viriale stress Main diagonal: tension-compression stress Off diagonal elements: shearing force PSE Garmisch-Partenkirchen 2016 Marco Jupé LZH 46
Image of page 46
MAEVA COATER (@CRM) Flat substrate model 0 30 60 90 120 150 180 210 240 270 300 330 10 20 30 40 50 60 70 80 10 20 30 40 50 60 70 80 0.000 1.000E+12 2.000E+12 3.000E+12 4.000E+12 5.000E+12 6.000E+12 7.000E+12 8.000E+12 9.000E+12 1.000E+13 1.100E+13 0 30 60 90 120 150 180 210 240 270 300 330 10 20 30 40 50 60 70 80 10 20 30 40 50 60 70 80 0.000 2.000E+12 4.000E+12 6.000E+12 8.000E+12 M11 M13 M31 M33 47 PSE Garmisch-Partenkirchen 2016 Marco Jupé LZH
Image of page 47