PSI - Issue 50

V.G. Degtiar et al. / Procedia Structural Integrity 50 (2023) 40–49 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 5. Plane 1, angle 15º, the distribution of defects across the size: (a) – linear scale; (b) – logarithmic scale (an increment for counting the number of defects in the histogram over the size is 0.001 mm 2 ); (c), (d) – REM-image and a map of defects of the considered sample surface of 13 х 4 mm 2 . Tables of fine-grained roughness used for the computation of heat exchange and C-C composite ablation from the FV surface are formed on the basis of tomography, electron microscopic data. Fine-grained roughness overlaps coarse-grained roughness, and the distribution of equivalent sandy-grained roughness over the ablated surface accumulatively corresponds to both C-C composite frame structure and the distribution of density over volume of a TPS C-C composite element. Earlier the distribution of pores, shells, defects was studied for 4KMS-L, 4KMS-LU, 4KMS-LG composites, and for 4KMS-L, 4KMS-LU there were also data on the distribution of density over volume, Kostin (2004), Degtiar et al. (2014), Degtiar et al. (2016), Degtiar et al. (2018), Degtiar et al. (2019), Degtiar, Saveliev et al. (2016), Degtiar et al. (2020). Models of the distribution of equivalent roughness over volume of the materials were constructed using Dirling correlation. Dirling correlation is of the following form