PSI - Issue 50

R.S. Akhmetkhanov et al. / Procedia Structural Integrity 50 (2023) 6–10 R.S.Akhmetkhanov / Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 4. Images of thermograms: (a) at deformation  1

ij ; (b) at deformation  2 ij

In these images (fig. 4) of the skeleton line profiles, there are areas with maximum temperature values. In accordance with the thermoplastic effect, we can say that in these areas of maximum local plastic strains - these are the areas of initial failure of the sample. As damage accumulates and cracks form, local stresses will be redistributed - the stress level throughout the entire volume of the OC will change. The newly appeared cracks will be stress concentrators, their areas will increase with the increase of their lengths. Fig.5 shows graphs of temperature changes (profile) of lines 1,2 and 3 in fig.4b. All these lines show that there are areas of maximum temperature ( T max1 , T max2 and T max3 ). Change of values T maxi and lengths of skeleton lines with increased temperature l i - are indicators of places of increase of plastic deformations and zones of possible failure of the sample.

Fig. 5. Images of the line profiles 1, 2 and 3 (Fig. 4): (a) pos.1; (b) pos.2; c - pos. 3

Let's calculate the average temperature of the i -th skeleton line