Solid-state cold spraying of FeCoCrNiMn high-entropy alloy: an insight into microstructure evolution and oxidation behavior at 700-900 °C

doi:10.1016/j.jmst.2020.06.041

Abstract

Abstract:

About 3 mm thick five-element equimolar high-entropy alloy (HEA) FeCoCrNiMn was successfully deposited by solid-state cold spraying (CS). The high-temperature oxidation behavior of the CSed HEA was investigated at 700-900 °C. Heat treatment was performed on the CSed HEA before oxidation to heal the incomplete interfaces between the deposited particles. Results show that the microstructure of the CSed HEA is characterized by grain refinement and abundant interparticle incomplete interfaces. Post-spray heat treatment promotes recrystallization and grain growth in the CSed HEA. After oxidation testing, the oxide scales are composed of multi-layers: a Mn₂O₃ (or Mn₃O₄) outer layer, a Mn-Cr spinel intermediate layer and a Cr₂O₃ inner layer. The CSed HEA exhibits higher parabolic rate constants and more favorable internal oxidation than the bulk HEAs that have similar compositions in the literature. Such a discrepancy becomes pronounced at higher temperatures. The grain refinement and numerous particle boundaries are responsible for such a distinctive performance of the CSed HEA.

Key words: Cold spray, High-entropy alloy, Oxidation, Isothermal heat treatment

Yaxin Xu, Wenya Li, Longzhen Qu, Xiawei Yang, Bo Song, Rocco Lupoi, Shuo Yin. Solid-state cold spraying of FeCoCrNiMn high-entropy alloy: an insight into microstructure evolution and oxidation behavior at 700-900 °C[J]. J. Mater. Sci. Technol., 2021, 68: 172-183.

Figures/Tables 18

Fig. 1. Schematic of cutting procedure of the CSed HEA.

Table 1 Chemical composition of the CSed FeCoCiNiMn HEA by EPMA analysis (at.%)*.

	Fe	Co	Cr	Ni	Mn
CSed FeCoCrNiMn	20.00 ± 0.62	19.58 ± 0.43	20.66 ± 0.38	19.05 ± 0.39	20.61 ± 0.69
H5M [19]	20.51	20.45	19.29	19.46	20.29
CoCrFeMnNi HEA [22]	20.55	20.26	19.41	19.46	20.10

Fig. 2. EBSD results of a single HEA particle: (a) image quality (IQ), (b) inverse pole figure (IPF) and (c) grain size.

Fig. 3. SEM images under back-scattered electron mode of the as-sprayed (a) and heat treated (b) FeCoCrNiMn.

Fig. 4. EBSD maps of the as-sprayed FeCoCrNiMn: (a) image quality, (b) grain structure.

Fig. 5. Data derived from EBSD maps of the as-sprayed FeCoCrNiMn: (a) misorientation distribution, (b) grain size distribution. The inserted graph in (b) is an enlarged view of grain size over 4 μm.

Fig. 6. EBSD maps of the heat treated CSed FeCoCrNiMn: (a) image quality, (b) grain structure.

Fig. 7. Data derived from EBSD maps of the heat treated CSed FeCoCrNiMn: (a) misorientation distribution, (b) grain size distribution. The inserted graph in (b) is an enlarged view of grain size over 4 μm.

Fig. 8. Phase structure of the CSed FeCoCrNiMn with and without heat treatment.

Fig. 9. Oxidation kinetics curves of the CSed FeCoCrNiMn during exposure at 700 °C (a, b), 800 °C (c, d) and 900 °C (e, f) for 100 h: (a, c, e) normal plots, (b, d, f) parabolic plots.

Table 2 Parabolic rate constant kp of the CSed FeCoCrNiMn in the present study vs. the values reported in literature for bulk HEA.

Material	Parabolic rate constant k_p (mg² cm^-4 h^-1)
Material	700 °C	800 °C	900 °C
CSed FeCoCrNiMn*	0.02028	0.0997	0.49226 (0-50 h)
CSed FeCoCrNiMn*	0.02028	0.0997	0.11197 (50-100 h)
FeCoNiCrMn HEA in Ref. [26]	0.0197	0.0600	0.1487
FeCoNiCrMn HEA in Ref. [23]	0.0184	0.054	0.104
CoFeCrMnNi [28]	0.0119	0.0432	0.0792

Fig. 10. Arrhenius plots of the parabolic oxidation rate constant kp by plotting the natural logarithm of kp versus reciprocal temperature. Our results are compared with oxidation data for pure manganese [35], H5M [23] and CrMnFeCoNi [26]. Q here refers to the apparent activation energy for oxidation (KJ/mol).

Fig. 11. Surface morphology of the oxide scales on the CSed FeCoCrNiMn after oxidation at 700 °C (a), 800 °C (b) and 900 °C (c) for 100 h, respectively. (The yellow circles in Fig. 9(a) indicate the interparticle boundaries.)

Fig. 12. Cross-sectional morphology of the oxide scales on the CSed FeCoCrNiMn after oxidation at 700 °C (a), 800 °C (b) and 900 °C (c) for 100 h, respectively.

Table 3 Chemical composition of the oxide scale in atomic percentage by EDS with standard deviation.

Alloy	Point	O	Cr	Mn	Fe	Co	Ni
700 °C	P1	52.4 ± 0.13	0.5 ± 0.05	46.0 ± 0.17	0.6 ± 0.10	0.3 ± 0.07	0.2 ± 0.07
700 °C	P2	45.1 ± 0.13	17.9 ± 0.13	31.8 ± 0.16	2.4 ± 0.11	1.5 ± 0.09	1.3 ± 0.09
800 °C	P1	53.2 ± 0.40	2.2 ± 0.26	39.6 ± 0.45	2.9 ± 0.53	1.2 ± 0.40	0.9 ± 0.42
	P2	51.8 ± 0.24	12.7 ± 0.28	30.1 ± 0.40	1.3 ± 0.28	2.1 ± 0.27	2.0 ± 0.29
	P3	47.7 ± 0.31	3.0 ± 0.23	54.4 ± 0.51	0.9 ± 0.39	1.1 ± 0.33	0.5 ± 0.37
	P4	29.7 ± 0.26	26.1 ± 0.40	15.9 ± 0.21	9.8 ± 0.19	9.3 ± 0.14	9.2 ± 0.11
900 °C	P1	50.6 (0.12)	0.3 (0.04)	33.4(0.14)	7.5(0.11)	6.9(0.11)	1.3(0.08)
	P2	51.3 (0.11)	18.4 (0.12)	25.2(0.13)	2.9(0.09)	1.2(0.07)	1.0(0.07)
	P3	44.4 (0.11)	1.4 (0.13)	51.7(0.11)	0.5(0.09)	0.9(0.04)	1.1(0.08)

Fig. 13. EDS mapping results of the elemental distribution of CSed FeCoCrNiMn after exposure at 900 °C for 100 h.

Fig. 14. XRD patterns of surface oxides at 700 °C, 800 °C and 900 °C for 100 h (a) and those performed at different positions from the outer oxide to the inner oxide at 900 °C (b).

Fig. 15. Oxidation mechanism of the CSed FeCoCrNiMn at 900 °C.

References 45

[1]	D.B. Miracle, O.N. Senkov, Acta Mater., 122 (2017), pp. 448-511. DOI URL
[2]	M. Vaidya, K.G. Pradeep, B.S. Murty, G. Wilde, S.V. Divinski, Acta Mater., 146 (2018), pp. 211-224. DOI URL
[3]	M.-H. Tsai, J.-W. Yeh, Mater. Res. Lett., 2 (2014), pp. 107-123. DOI URL
[4]	A. Anupam, S. Kumar, N.M. Chavan, B.S. Murty, R.S. Kottada, J. Mater. Res., 34 (2019), pp. 796-806. DOI PMID
[5]	S. Yin, W. Li, B. Song, X. Yan, M. Kuang, Y. Xu, K. Wen, R. Lupoi, J. Mater. Sci. Technol., 35 (2019), pp. 1003-1007. DOI URL
[6]	S.Y. Chen, Y. Tong, P.K. Liaw, Entropy, 20 (2018), p. 937. DOI URL
[7]	B. Li, B. Qian, Y. Xu, Z.Y. Liu, F.Z. Xuan, Mater. Lett., 252 (2019), pp. 88-91. DOI URL
[8]	K.-C. Cheng, J.-H. Chen, S. Stadler, S.-H. Chen, Appl. Surf. Sci., 478 (2019), pp. 478-486. DOI URL
[9]	X. Niu, L. Wang, D. Sun, J. Dong, C. Li, J. Dalian Univ. Technol., 53 (2013), pp. 689-694.
[10]	X. Wang, Y. Sun, R. Li, L. Wang, M. Chen, Hot Working Technology, 44 (12) (2015), pp. 174-181 (in Chinese).
[11]	M.-H. Hsieh, M.-H. Tsai, W.-J. Shen, J.-W. Yeh, Surf. Coat. Technol., 221 (2013), pp. 118-123. DOI URL
[12]	W.-y. Huo, H.-f. Shi, X. Ren, J.-y. Zhang, Adv. Mater. Sci. Eng., 2015 (2015), pp. 1-5.
[13]	Q. Ye, K. Feng, Z. Li, F. Lu, R. Li, J. Huang, Y. Wu, Appl. Surf. Sci., 396 (2017), pp. 1420-1426. DOI URL
[14]	W.Y. Li, H. Assadi, F. Gaertner, S. Yin, Crit. Rev. Solid State Mat. Sci., 44 (2019), pp. 109-156. DOI URL
[15]	H. Assadi, F. Gärtner, T. Stoltenhoff, H. Kreye, Acta Mater., 51 (2003), pp. 4379-4394. DOI URL
[16]	W. Li, C. Cao, S. Yin, Prog. Mater. Sci., 110 (2020), 100633. DOI URL
[17]	Y.-K. Wei, Y.-J. Li, Y. Zhang, X.-T. Luo, C.-J. Li, Corros. Sci., 138 (2018), pp. 105-115. DOI URL
[18]	S. Kumar, M. Ramakrishna, N.M. Chavan, S.V. Joshi, Acta Mater., 130 (2017), pp. 177-195. DOI URL
[19]	X.-T. Luo, Y.-K. Wei, Y. Wang, C.-J. Li, , Mater. Des., 85 (2015), pp. 527-533. DOI URL
[20]	A. Chaudhuri, Y. Raghupathy, D. Srinivasan, S. Suwas, C. Srivastava, Acta Mater., 129 (2017), pp. 11-25. DOI URL
[21]	J. Henao, A. Concustell, S. Dosta, G. Bolelli, I.G. Cano, L. Lusvarghi, J.M. Guilemany, Acta Mater., 125 (2017), pp. 327-339. DOI URL
[22]	J. Lehtonen, H. Koivuluoto, Y. Ge, A. Juselius, S.-P. Hannula, Coatings, 10 (2020), p. 53. DOI URL
[23]	W. Kai, C.C. Li, F.P. Cheng, K.P. Chu, R.T. Huang, L.W. Tsay, J.J. Kai, Corros. Sci., 121 (2017), pp. 116-125. DOI URL
[24]	T.-K. Tsao, A.-C. Yeh, C.-M. Kuo, H. Murakami, Entropy, 18 (2016), p. 62. DOI URL
[25]	W. Kai, C.C. Li, F.P. Cheng, K.P. Chu, R.T. Huang, L.W. Tsay, J.J. Kai, Corros. Sci., 108 (2016), pp. 209-214. DOI URL
[26]	G. Laplanche, U.F. Volkert, G. Eggeler, E.P. George, Oxid. Met., 85 (2016), pp. 629-645. DOI URL
[27]	B. Gorr, F. Mueller, H.J. Christ, T. Mueller, H. Chen, A. Kauffmann, M. Heilmaier, J. Alloy Compd., 688 (2016), pp. 468-477.
[28]	D. Huang, J. Lu, Y. Zhuang, C. Tian, Y. Li, Corros. Sci., 158 (2019), 108088. DOI URL
[29]	K.Y. Tsai, M.H. Tsai, J.W. Yeh, Acta Mater., 61 (2013), pp. 4887-4897. DOI URL
[30]	X.-T. Luo, C.-X. Li, F.-L. Shang, G.-J. Yang, Y.-Y. Wang, C.-J. Li, Surf. Coat. Technol., 254 (2014), pp. 11-20. DOI URL
[31]	C. Lee, J. Kim, J. Therm. Spray Technol., 24 (2015), pp. 592-610. DOI URL
[32]	M.R. Rokni, C.A. Widener, V.R. Champagne, J. Therm. Spray Technol., 23 (2013), pp. 514-524. DOI URL
[33]	K. Kang, H. Park, G. Bae, C. Lee, J. Mater. Sci., 47 (2012), pp. 4053-4061. DOI URL
[34]	K. Kim, M. Watanabe, J. Kawakita, S. Kuroda, Scr. Mater., 59 (2008), pp. 768-771. DOI URL
[35]	J. Païdassi, A. Echeverría, Acta Metall., 7 (1959), pp. 293-295. DOI URL
[36]	Z. Yang, J.-t. Lu, Z. Yang, Y. Li, Y. Yuan, Y.-f. Gu, Corros. Sci., 125 (2017), pp. 106-113. DOI URL
[37]	Y.-X. Xu, J.-T. Lu, X.-W. Yang, J.-B. Yan, W.-Y. Li, Corros. Sci., 127 (2017), pp. 10-20. DOI URL
[38]	Thermodynamics data comes from HSC Chemistry 6.
[39]	MnO rt thermal expansion: Datasheet from "PAULING FILE Multinaries Edition - 2012, in SpringerMaterials (https://materials.springer.com/isp/physical-property/docs/ppp_b7c2348f95159a6cbe3e14bad25443fa), in: P. Villars, F. Hulliger (Eds.) Springer-Verlag Berlin Heidelberg & Material Phases Data System (MPDS), Switzerland & National Institute for Materials Science (NIMS), Japan.
[40]	Chromium sesquioxide(Cr2O3): thermal expansion, density, melting point: Datasheet from Landolt-Börnstein - Group III Condensed Matter · Volume 41D: Non-Tetrahedrally Bonded Binary Compounds II, in SpringerMaterials (https://dx.doi.org/10.1007/10681735_651), in: O. Madelung, U. Rössler, M. Schulz (Eds.) Springer-Verlag Berlin Heidelberg.
[41]	N. Birks, G.H. Meier, F. Pettit, Introduction to the High Temperature Oxidation of Metals (Second edition), Cambridge University Press, New York(2006).
[42]	V. Patel, W.Y. Li, A. Vairis, V. Badheka, Crit. Rev. Solid State Mat. Sci., 44 (2019), pp. 378-426. DOI URL
[43]	C. Huang, W. Li, Y. Feng, Y. Xie, M.-P. Planche, H. Liao, G. Montavon, Mater. Charact., 125 (2017), pp. 76-82. DOI URL
[44]	K. Yang, W. Li, C. Huang, X. Yang, Y. Xu, J. Mater. Sci. Technol., 34 (2018), pp. 2167-2177. DOI URL
[45]	K. Yang, W. Li, Y. Xu, X. Yang, J. Alloy Compd., 774 (2018), pp. 1223-1232. DOI URL