PSI - Issue 50

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

43

4

Tsn k k k   Ts

(4)

Tsp

where Tsp k  – scatters due to different distributions of pores, shells, other defects, which are illustrated in Fig. 3, Degtiar et al. (2016), from the nominal.

Fig. 3. Electron micrographic shots of a sample of MKU-4M- 7 composite cut at 15° to the axial direction: (a) 50-fold increase; (b) 100-fold increase; (c) 300-fold increase; (d) 3000-fold increase. Designating indexes 1 and 2 to two slightly different values of density one can get

k



Тsn k k k  Тsi

Vn P P P   1 Vi

 



,

1,2

a

a

i

Тspi









Тsn

i

n

Vn

k

n 

Тsn

(5)

k

 

Тs k k k k   2 1 Тs

V P P P P   1

    1

1

Тsp







Тsn

Vn

n

k

2

2

2

Тsp

Тsn

V

Vn

n

where  – density parameter, the distribution of which over a TPS C-C composite element, taken by tomography, is given as initial data for computing ablated shapes. A rig implementing X-ray tomography in conical beams was used for tomography study. The COMET-450 X-ray unit with maximum voltage up to 450 keV was used as an emitter. A flat panel detector (the Perkin Elmers camera, 2048 х 2048 pixels, 0.2 х 0.2 mm 2 ) was utilized for detecting. An object (sample, piece) was put on a centering seat. The DELKEN-automazione system moved and circled the object ensuring the accuracy in height and concentricity no less than 0.01 mm. An aluminum compensator performed X-raying and reconstruction. The general view of a system getting projection data can be seen in Fig. 4.