PSI - Issue 40

Vladimir Arkhipov et al. / Procedia Structural Integrity 40 (2022) 27–31 Vladimir Arkhipov et al. / Structural Integrity Procedia 00 (2022) 000 – 000

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Nozzle displacement of 2 mm resulted in the appearance of areas exposed to particles exposure and heated air flow three times, while at displacement of 3 mm, the surface was subjected to a more uniform treatment no more than two times Table 1.

Table 1. Influence of nozzle displacement on the spraying area.

Area mm 2 exposed to particles, times

Nozzle displacement, mm

Overlap coefficient %

1

2

3

2 3

64 55

20 74

90

112.5

148.5

-

The analysis of the diffraction lines broadening in order to determine the fine crystal structure parameters (block size, microstrains) is carried out using PDXL software (Rigaku) by the Rietveld method. The instrumental broadening was taken into account by shooting a reference — lanthanum hexaboride (LaB 6 ), which does not exhibit physical broadening. The diffraction patterns analysis is carried out on the basis PDXL software product (Rigaku) using the PDF-2 database. The quantitative analysis is carried out using Rietveld method implemented in the PDXL software package (Rigaku). The coatings phase composition of the Cu-Zn system is studied on Rigaku Ultima IV multifunctional X-ray diffractometer using CuKα radiation in the geometry of a parallel beam. To form a parallel beam, X -ray optics in the form of a multilayer parabolic mirror is used. Diffraction patterns are shoot in a symmetric mode, the scanning range is 2θ from 20 to 120, “step 0.05°”, detector speed “3° / min”. 3. Research results X-ray diffraction phase and micro-X-ray spectral analyzes revealed that the coating structure consisted of metals ( copper, zinc) and electronic type compounds "ε" and "γ" - phases inherent in copper and zinc alloys (brass) Table 2.

Table 2. Influence of the air flow temperature on the coating phase composition.

Mass fraction of metals and phases, %

Cu

Zn

ε – phase

γ - phase

Т°С

Nozzle displacement, mm

2

3

2

3

2

3

2

3

270 360 540

-

- - -

87.9±1.0 62.0±0.9 40.5±0.8

83.8±0.8 69.0±0.7 56.0±0.8

1.44±0.17

1.3±0.1 12.6±0.6 24.0±0.6

5.3±0.9 7.9±0.8 11.4±0.7

8.5±0.9 10.4±0.5 12.0±0.7

7.9±0.6 9.0±0.6

17.0±2.0 33.0±0.2

The study of the CSR elements of the coating under consideration revealed a significant effect on them of the technological modes of spraying. When the coating was sprayed, the initial copper particles were refined during the coating process from 35 μm to 200 nm, the overlapping of layers by 55% further increases the crushing, which was 21 nm, the overlap by 64% increased the crushing not so significantly and amounted to 90 nm. The air flow temperature change from 270˚C to 360˚C did not affect the CSR at 64% overlap and was about 100 nm, but increased the particle size from 21 to 62 nm at 55% overlap. The temperature of 450°C led to the particle size decrease at 64% overlap to 64 nm and did not affect particle size at 55% overlap. The copper diffusion into zinc with overlap of 64% is 1.14x10 -12 m 2 /s, and with overlap of 55% it is 0.11x10 -13 m 2 /s by Arkhipov et al. (2020, 2021). The CSR of the el ectronic compound of the ε phase was 80 nm with overlap of 64% and increased with temperature increase; with overlap of 55% it decreased, respectively, from 36 to 21 nm with temperature increase