13th International Conference on Fracture June 16–21, 2013, Beijing, China -8- Figure 10. Decomposition of the thermal problem Figures 11 and 12 show the normal stress in the direction of the y axis. The thermal effect on the stress intensity factor, Ktemp, is calculated from the case (a) with the Green function and the stress field along the x axis calculated with the case (b) : x a x a x K a temp d ( ) 2 0 2 2 (10) with a the crack length. The value of the thermal correction of the stress intensity factor Ktemp for the plane problem with an centered through crack for a line heat source of 153Wm-1 is about -0.316MPa m. Figure 11. Normal stress field in the direction Figure 12. Normal stress in the direction of the y axis of the y axis distributed along the x axis 2. Conclusion The correction on the mode one stress intensity factor, Ktemp, determined in the two previous sections is a value superimposed on the usual stress intensity factor due to the fatigue cyclic loading, noted Kcyc(t), which varies at each cycle between a maximum, Kcyc,max , and a minimum, Kcyc,min, of the stress intensity factor. As written before, due to the compressive thermal stresses around the
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