Effect of annealing treatment on microstructures, mechanical properties and cavitation erosion performance of high velocity oxy-fuel sprayed NiCoCrAlYTa coating

doi:10.1016/j.jmst.2020.03.030

Abstract

Abstract:

The mechanical parts serving in the marine environment are up against the dual damage of corrosion and cavitation erosion, so the NiCoCrAlYTa coating with excellent corrosion resistance is successfully prepared by high velocity oxy-fuel (HVOF) sprayed technology to protect the equipment from deterioration. The chemical composition and mechanical properties as well as the microstructure evolution of the coating before and after annealing treatment are studied. At the same time, the influence of annealing treatment on the corrosion and cavitation erosion behaviors of the coating is investigated, as well. The NiCoCrAlYTa coating mainly contains γ-Ni, β-NiAl, and γ’-Ni₃Al phases. During the deposition, the microcrystals or incomplete crystals generate in the interior of the coating because of the large temperature difference and impact force. Meanwhile, there is twin crystal structure in the as-spayed coating. After annealing treatment, the growth of grains and the segregation of reactive elements improve interface strength and inhibit the formation of micro-defects in the coating. The annealing temperature is of significance to the microstructure, mechanical properties, anti-corrosion and cavitation erosion resistance of the coating. This study provides a combined approach toward improving the corrosion and cavitation erosion resistance of NiCoCrAlYTa coatings.

Key words: iCoCrAlYTa coatings, Annealing treatment, Microstructure, Mechanical properties, Cavitation erosion

Enkang Hao, Yulong An, Xia Liu, Yijing Wang, Huidi Zhou, Fengyuan Yan. Effect of annealing treatment on microstructures, mechanical properties and cavitation erosion performance of high velocity oxy-fuel sprayed NiCoCrAlYTa coating[J]. J. Mater. Sci. Technol., 2020, 53: 19-31.

Figures/Tables 20

Table 1 Parameters for HVOF spraying process.

Parameters	Value
Oxygen flow (m³/h)	19.8
Natural gas flow (m³/h)	13.5
Air flow (m³/h)	18.7
Powder feed rate (g/min)	25
Gun speed (mm/s)	800
Spraying distance (cm)	30

Table 2 The chemical composition (g/L) of the artificial seawater*.

NaCl	Na₂SO₄	MgCl₂	CaCl₂	SrCl₂	KCl	NaHCO₃	KBr	H₃BO₃	NaF
24.53	4.09	5.20	1.16	0.025	0.695	0.201	0.101	0.027	0.003

Fig. 1. SEM image and XRD pattern (a) as well as particles size (b) of the as-received powders; SEM image and XRD pattern (c) as well as the nano-indentation curve (d) of as-sprayed coating.

Fig. 2. SEM (a) and FESEM (b) images of cross-section as well as the SEM image (c) of polished-surface of the as-sprayed coating.

Fig. 3. Optical images of the samples: SRT (a), S600 (b), S800 (c), S1000 (d).

Fig. 4. Micro-hardness (a) and Nano-indentation (b) of the coatings.

Table 3 The parameters of nano-indentation curves.

Specimens	Mechanical properties
Specimens	H_IT (GPa)	E* (GPa)	E_str	R_def
S₆₀₀	12.84	288.07	0.04457	0.02551
S₈₀₀	15.82	293.53	0.05390	0.04595
S₁₀₀₀	22.24	281.50	0.07964	0.1388

Fig. 5. Electrochemical measurements of NiCoCrAlYTa coatings: Nyquist plots (a, b), Bode plots (c, d).

Table 4 The EIS fitting results of the specimens.

Specimens	EIS fitting results
Specimens	R_s (? cm²)	R_f /10⁴ (? cm²)	CPE-T₁ (?^-1 cm^-2·sⁿ)	CPE-P₁	R_ct /10⁶ (? cm²)	CPE-T₂ (?^-1 cm^-2·sⁿ)	CPE-P₂
S_RT	113.9	1.668	3.200 × 10^-6	0.8756	4.661	1.336 × 10^-6	0.6666
S₆₀₀	165.4	23.78	1.546 × 10^-7	0.9163	32.37	1.258 × 10^-6	0.6214
S₈₀₀	113.5	65.01	1.953 × 10^-8	0.9672	240.9	4.647 × 10^-8	0.3661
S₁₀₀₀	58.31	94.64	3.295 × 10^-9	0.9459	2.278 × 10³	6.672 × 10^-9	0.8825

Fig. 6. Cumulative volume loss and cavitation erosion rate as a function of time for the specimens after cavitation erosion in seawater: cumulative volume loss (a), cavitation erosion rate (b).

Fig. 7. XRD pattern (a) and Raman spectra (b) of the samples.

Fig. 8. FESEM morphologies of the coatings: S600 (a), S800 (b), S1000 (c).

Fig. 9. FESEM sectional morphologies of the coatings: S600 (a), S800 (b), S1000 (c).

Fig. 10. SEM images of surfaces of the coatings after cavitation erosion for 10 h: SRT (a), S600 (b), S800 (c), S1000 (d).

Fig. 11. FESEM sectional images of the coatings after cavitation erosion in seawater for 10 h: SRT (a), S600 (b), S800 (c), S1000 (d).

Fig. 12. EBSD maps for SRT and S800: 0-1 μm grains of SRT (a) and S800 (b); grain size distribution (c); IPF maps of SRT (d) and S800 (e); misorientation angle distribution (f).

Fig. 13. TEM (a) and HRTEM images of area “A” (b) and “B” (c) as well as diffracting patterns (d-f) of the cross-section of SRT.

Table 5 EDS results of the region in Fig. 13(a) (element composition: mass fraction, %).

Area for analysis	Ni	Co	Cr	Al	Ta	Y	O
Spectra 1	38.83	18.78	19.00	13.53	1.41	0.21	8.23
Spectra 2	33.75	16.92	17.71	11.93	1.09	0.21	18.40
Spectra 3	38.02	19.31	18.07	13. 25	1.26	0.25	9.84
Spectra 4	4.29	5.62	15.36	8.57	1.12	0.26	64.79

Fig. 14. TEM image (a); HRTEM images of area “A” (b) and “B” (c) as well as “C” (d); diffracting patterns (e-g); line-scanning element composition (h) covering the yellow line range in image (a) of the cross-section of S800.

Fig. 15. Schematic diagram for the process of the NiCoCrAlYTa coating annealed at 800 ℃ (a), and the damage process of cavitation corrosion of the coating before (b-d) and after (e-g) the annealing treatment.

References 37

[1]	G. Awadi, S. Samad, E. Elshazly, Appl. Surf. Sci. 378 (2016) 224-230. DOI URL
[2]	X. Peng, S. Jiang, J. Gong, X. Sun, C. Sun, J. Mater. Sci. Technol. 32 (2016) 587-592.
[3]	J. Shi, A. Zheng, Z. Lin, R. Chen, J. Zheng, Z. Cao, Mater. Sci. Eng. A 740-741 (2019) 130-136. DOI URL
[4]	J. Liang, Y. Liu, J. Li, Y. Zhou, X. Sun, J. Mater. Sci. Technol. 35 (2019) 344-350. DOI URL
[5]	Y. Han, B. Zhang, X. Gu, X. Qiang, Y. Chu, X. Li, Surf. Coat. Technol. 368 (2019) 202-214. DOI URL
[6]	L. Yang, Z. Zou, Z. Kou, Y. Chen, G. Zhao, X. Zhao, F. Guo, P. Xiao, Acta Mater. 139 (2017) 122-137. DOI URL
[7]	W. Zhu, L. Yang, J. Guo, Y. Zhou, C. Lu, Int. J. Plast. 64 (2015) 76-87. DOI URL
[8]	M. Ansari, R. Razavi, M. Barekat, H. Man, Corros. Sci. 118 (2017) 168-177. DOI URL
[9]	Y. Chen, X. Zhao, P. Xiao, Acta Mater. 159 (2018) 150-162. DOI URL
[10]	X. Liu, Y. An, X. Zhao, S. Li, W. Deng, G. Hou, Y. Ye, H. Zhou, J. Chen, Corros. Sci. 112 (2016) 696-709.
[11]	H. Yang, J. Zou, Q. Shi, M. Dai, S. Lin, W. Du, L. Lv, Corros. Sci. 153 (2019) 162-169. DOI URL
[12]	Y. Ma, A. Ardell, Scr. Mater. 52 (2005) 1335-1340. DOI URL
[13]	E. Hao, Y. An, X. Zhao, H. Zhou, J. Chen, Appl. Surf. Sci. 462 (2018) 194-206. DOI URL
[14]	C. Xiao, Y. Han, Scr. Mater. 41 (1999) 475-480. DOI URL
[15]	J. Singh, J. Mazumder, Metall. Trans. A 19 (1988) 1981-1990. DOI URL
[16]	G. Jackson, W. Sun, D. McCartney, Mater. Sci. Eng. A 754 (2019) 479-490.
[17]	R. Mahesh, R. Jayaganthan, S. Prakash, J. Mater. Process. Technol. 209 (2009) 3501-3510.
[18]	K. Yuan, R. Peng, X. Li, S. Johansson, Y. Wang, Surf. Coat. Technol. 261 (2015) 86-101.
[19]	L. Qiao, Y. Wu, S. Hong, J. Cheng, Ultrason. Sonochem. 52 (2019) 142-149. DOI URL PMID
[20]	W. Deng, Y. An, G. Hou, S. Li, H. Zhou, J. Chen, Ultrason. Sonochem. 46 (2018) 1-9. URL PMID
[21]	M. Romero, A. Tschiptschin, C. Scandian, Wear 426-427 (2019) 518-526. DOI URL
[22]	T. Amann, M. Waidele, A. Kailer, Tribol. Int. 124 (2018) 238-246.
[23]	Y. Wang, B. Lebon, I. Tzanakis, Y. Zhao, K. Wang, J. Stella, T. Poirier, G. Darut, H. Liao, M. Planche, Ultrason. Sonochem. 52 (2019) 336-343. URL PMID
[24]	Y. Wang, J. Liu, N. Kang, G. Darut, T. Poirier, J. Stella, H. Liao, M. Planche, Tribol. Int. 102 (2016) 429-435.
[25]	Z. Qin, Q. Zhang, Q. Luo, Z. Wu, B. Shen, L. Liu, W. Hu, Corros. Sci. 139 (2018) 255-266.
[26]	J. McCollum, M. Pantoya, N. Tamura, Acta Mater. 103 (2016) 495-501.
[27]	M. Chen, Z. Zou, Y. Lin, H. Li, G. Wang, Y. Ma, Mater. Charact. 151 (2019) 445-456.
[28]	D. Lee, J. Lee, Y. Zhao, Z. Lu, J. Suh, J. Kim, U. Ramamurty, M. Kawasaki, T. Langdon, J. Jang, Acta Mater. 140 (2017) 443-451.
[29]	H. Yu, Y. Sun, Z. Wan, H. Zhou, L. Hu, J. Alloys Compd. 741 (2018) 231-239.
[30]	L. Aissani, M. Fellah, L. Radjehi, C. Nouveau, A. Montagne, A. Alhussein, Surf. Coat. Technol. 359 (2019) 403-413.
[31]	L. Zhang, H. Peng, Q. Qin, Q. Fan, S. Bao, Y. Wen, J. Alloys Compd. 746 (2018) 45-53.
[32]	G. ASTM, 32-16, Philadelphia, PA, 2016.
[33]	Y. Han, H. Chen, D. Gao, G. Yang, B. Liu, Y. Chu, J. Fan, Y. Gao, J. Therm. Spray Technol. 26 (2017) 1758-1775.
[34]	C. Zhu, P. Li, X. Wu, Ceram. Int. 42 (2016) 7708-7716.
[35]	B. Cui, D. Jayaseelan, W. Lee, Acta Mater. 59 (2011) 4116-4125.
[36]	J. Wang, Y. Zhou, T. Liao, J. Zhang, Z. Lin, Scr. Mater. 58 (2008) 227-230. DOI URL
[37]	D. Li, D. Chen, P. Liang, Ultrason. Sonochem. 35 (2017) 375-381. DOI URL PMID