PSI - Issue 30

V.P. Gulyaev et al. / Procedia Structural Integrity 30 (2020) 40–44 Gulyaev V.P., Petrov P.P., Stepanova K.V. / Structural Integrity Procedia 00 (2020) 000–000

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Fig.1. General view and geometric dimensions of samples for cyclic loading.

Table 1. Parameters of the cyclic loading of steel 09G2S samples. Loads Maximum cycle stress σ max Number of cycles

Load frequency, Hz

1

0,5 σ 0,2

40000

3

2

0,7 σ 0,2

40000

3

40000

3

3

0,9 σ 0,2

The X-ray analysis of 2 batches of samples was performed at 3 points of the effective part of the samples surface (see Fig. 2a). Analysis of the third batch of samples, pre-cyclically loaded with 40,000 cycles with a maximum cycle stress amplitude of σ max = 0,9 σ 0,2 , was conducted at 6 points on the samples surface, identified by the coordinates indicated in Fig. 2b, from 2 sides of the samples effective part. All samples after X-rays were stored indoor for 10 years. In 2019, X-ray photography of those samples was performed on a Rigaku Ultima IV diffractometer according to the scanning scheme with Bragg - Brentano focusing in Co К α radiation (wavelength λ = 1.790255 angstrom). The width of the slit restricting the incident beam horizontally is 10 mm, vertically is 0.50 mm; Seller slits on the incident and diffracted beams - 0.50 mm; the width of the slit restricting the diffracted beam vertically in front of the receiving slit is 0.50 mm. The operating mode of the X-ray source: U=40kV; I=30mA; scanning speed is 0.1 deg/min with 0.01 deg. interval.

Fig.2. Location of the X-ray points of cyclically loaded 09G2S steel samples.