The Behavior at Corrosion and Fatigue of the Aluminum Alloy, Coated with a Cobalt Base Alloy, Deposited by Thermal Spraying in Electric Arc

Abstract:

The present investigation has been conducted in order to study the fatigue and corrosion fatigue behaviour of an aluminium alloy (99,5%Al) substrate coated with a 106 MXC deposited by thermal spraying in electric arc. It has been determined that the deposition of such a coating on the aluminum substrate gives rise to significant gains in fatigue life in comparison with the uncoated substrate, when testing is carried out both in air and in a 3,5 wt.% NaCl solution. It has been shown that during testing in air, the fatigue gain ranges between ~131 and 186%, depending on the maximum alternating stress applied to the material. Larger fatigue gains are associated with low alternating stresses. Also, when fatigue testing is conducted in the NaCl solution, the gain in fatigue resistance varies between ~124 and 159%. Fatigue cracks have been observed to initiate at the coating surface and then grow towards the substrate after propagating through the entire coating thickness. Although in the present work residual stresses were not measured, it is believed that the gain in fatigue life of the coating–substrate system is due to the presence of compressive residual stresses within the coating which hinder fatigue crack propagation. The deposition of the coating does not give rise to significant changes in the static mechanical properties and hardness of the aluminum alloy substrate.

• Periodical: Applied Mechanics and Materials (Volumes 809-810)
• Pages: 584-589
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.809-810.584
• Online since: November 2015
• Authors: Stefan Lucian Toma, Iulian Ionita, Lucian Eva, Costică Bejinariu, Bogdan Istrate, Bogdan Florin Toma*
• Keywords: Aluminium, Corrosion Fatigue, Thermal Spray

References

[1] B. Meyers, S. Lynn, ASM Handbook, Surface Engineering, vol. 5, ASM International, Materials park, OH, (1994).

[2] St.L. Toma, C. Bejinariu, D.A. Gheorghiu, and C. Baciu -The improvement of the physical and mechanical properties of steel deposits obtained by thermal spraying in electric arc - Advanced Materials Research. 814 (2013) 173-179.

DOI: 10.4028/www.scientific.net/amr.814.173

[3] J. Wilden, J.P. Bergmann, S. Jahn, S. Knapp, F. van Rodijnen, and G. Fischer, Investig. about the Cr. steel wire arc spray pro. and the result. coat. prop., J. Therm. Spray Technol. 16, 5-6 (2007) 759-767.

DOI: 10.1007/s11666-007-9114-8

[4] St.L. Toma, The influence of jet gas temperature on the characteristics of steel coating obtained by wire arc spraying, Surf & Coat. Technol. 220 (2013) 261–265.

DOI: 10.1016/j.surfcoat.2012.12.006

[5] A. Pourmousa, J. Mostaghimi, A. Abedini, and S. Chandra, Particle Size Distribution in a Wire-Arc Spraying System, J. Therm. Spray Technol. 14, 4 (2005) 502-510.

DOI: 10.1361/105996305x76522

[6] P.M. Natishan, S.H. Lawrence, R.L. Foster, J. Lewis, B.D. Sartwell, Salt fog corr. behavior of HVOF thermal spray coat. Compar. to electrodeposited hard chromium Surf. Coat. Technol. 130 (2000) 218.

DOI: 10.1016/s0257-8972(00)00671-x

[7] B.D. Sartwell, K.O. Legg, J. Schell, J. Sauer, P. Natishan, D. Dull, J. Falkowski, Validation of HVOF WC/Co thermal spray coatings as a replacement for hard chrome plating on aircraft landing gear NRL/MR/ 6170-04-8762, Nav. Res. Laboratory, Washington, DC, USA, (2004).

DOI: 10.21236/ada607046

[8] Şt. A. Irimiciuc, M. Agop, P. Nica, S. Gurlui, D. Mihaileanu, St. Toma, C. Focsa - Dispersive effects in laser ablation plasmas, Jpn. J. Appl. Phys. 53 (2014) 116202.

DOI: 10.7567/jjap.53.116202

[9] B.D. Sartwell, K. Legg, P.E. Bretz, Proc. Aerospace Plating and Metal Finishing Forum, American Electroplaters and Surf. Finishers Society, Cincinnati, OH, USA, March 2000, p.131.

[10] Standard methods of tension testing wrought and cast aluminum and magnesium alloys products, B 557, Annual Book of ASTM Stand., Vol. 03. 01, ASTM, Philadelphia, 1984, p.82.

[11] ASTM E 206-72, Standard definitions of terms relating to fatigue testing and the statistical analysis of fatigue data, (1979).

[12] A.L. Johnston, A.C. Hall, and J.F. McCloskey, Effect of Process Inputs on Coating Properties in the Twin-Wire Arc Zinc Process,J. Therm. Spray Technol. 22, 6 (2013) 856-863.

DOI: 10.1007/s11666-013-9949-0

[13] St.L. Toma, D.A. Gheorghiu, S. Radu, and C. Bejinariu, - The influence of the diffusion on adherence of the 60t deposits obtained through thermal spraying in electric arc, Applied Mechanics and Materials. 371 (2013) 270-274.

DOI: 10.4028/www.scientific.net/amm.371.270

[14] Technical Data Buletin Praxair & Tafa (2010) File 1. 9. 1. 2 – 106MXC (K10320).

[15] J.A. Marin de Camargo, H.J. Cornelis, V.M.O. Hilário Cioffi, M.Y. Pitanga Costa, Coat. residual stress effects on fatigue perform. of 7050-T7451 aluminum alloy, Surf. Coat. Technol. 201 (2007) 9448.

DOI: 10.1016/j.surfcoat.2007.03.032

[16] C.J. Villalobos-Gutiérrez, A. Piñeiro, M.H. Staia, D. Chicot, E.S. Puchi-Cabrera, et. al, Fatig. and corr. fatig . behav. of an AA6063-T6 aluminum alloy coated with a WC–10Co–4Cr alloy deposited by HVOF thermal spraying, Surf. Eng. 202, 4 (2008).

DOI: 10.1016/j.surfcoat.2008.04.044

[17] R.T.R. McGrann, D.J. Greving, and other, The effect of resid. stress in HVOF tungsten carbide coa. on the fatig. life in bend. of thermal spray coat. alum., Surf. Coat. Technol. 108–109 (1998) 546-552.

DOI: 10.1361/105996398770350774

[18] G. Bolelli, R. Giovanardi, L. Lusvarghi, T. Manfredini, Corrosion resist. of HVOF-sprayed coatings for hard chrome replacement, Corros. Sci. 48 (11) (2006) 3375.

DOI: 10.1016/j.corsci.2006.03.001