Fabrication and Characterization of Nanostructure Functionally Graded Ni-P Electroless Coating

Document Type: Research Paper


1 Young Researchers and Elite Club, Najafabad Branch, Islamic Azad University, Najafabad, Iran

2 Department of Materials Engineering, Isfahan University of Technology, Isfahan, Iran


In this research, novel functionally graded Ni-P coating was deposited with electroless process. The content of phosphorus was controlled to change gradual through the thickness of the coating. During the plating, bath temperature and pH were changed at specified intervals to obtain functionally graded structure. To compare the properties of functionally graded coating with Ni-P single-layer coatings, three types of coatings with different phosphorus contents were also deposited. Microstructure and phase composition of coatings were studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffractometry (XRD). The mechanical properties and tribological behavior of coatings were also investigated. Low phosphorus and medium phosphorus single-layer coatings had fully crystalline and amorphous-crystalline structures, respectively. While high phosphorus coating appeared to have a fully amorphous structure. TEM images showed that low phosphorus coating had nano-crystalline structure. Results of nano-indentation test showed gradual changes in hardness profile in cross-section of functionally graded coating due to the gradual changes of phosphorus content in the thickness of this coating. According to the wear test data, medium phosphorus coating had minimum wear resistance. Functionally graded coatings had better wear resistance than single-layer coatings.


Main Subjects

[1]    A. Zarebidaki and S. R. Allahkaram, “Porosity measurement of electroless Ni–P coatings reinforced by CNT or SiC particles,” Surf. Eng., vol. 28, pp. 400–405, 2012.

[2]    C. L. Ban, X. Shao, and L. P. Wang, “Ultrasonic irradiation assisted electroless Ni–P coating on magnesium alloy,” Surf. Eng., vol. 30, pp. 880–885, 2014.

[3]    M. H. Sadhir, M. Saranya, M. Aravind, A. Srinivasan, A. Siddharthan, and N. Rajendran, “Comparison of in situ and ex situ reduced graphene oxide reinforced electroless nickel phosphorus nanocomposite coating,” Appl. Surf. Sci., vol. 320, pp. 171–176, 2014.

[4]    S. Alirezaei, S. M. Monirvaghefi, A. Saatchi, and A. Motallebzadeh, “High temperature tribology of nanocrystalline Ni – P – Ag coating,” Surf. Eng., vol. 29, no. 4, pp. 306–311, 2013.

[5]    L. L. Wang, H. J. Chen, and Z. L. Chen, “Study on post‐treatments for electroless Ni–P coating,” Surf. Eng., vol. 27, pp. 57–60, 2011.

[6]    S. H. Park and D. N. Lee, “A study on the microstructure and phase transformation of electroless nickel deposits,” J. Mater. Sci., vol. 23, no. 5, pp. 1643–1654, 1988.

[7]    A. W. Goldstein, W. Rostoker, and J. J. Rezek, “Electron microscope study of the nucleation and growth of electroless cobalt and nickel,” J. Electrochem. Soc., vol. 119, pp. 1614–1619, 1972.

[8]    E. Vafaei-Makhsoos, E. L. Thomas, and E. L. Toth, “Electron microscopy of crystalline and amorphous Ni-P electrodeposited films: in-situ crystallization of an amorphous solid,” Metall. Trans. A, vol. 9, pp. 1449–1460, 1978.

[9]    B. Jiang, L. Xiao, S. Hu, J. Peng, H. Zhang, and M. Wang, “Optimization and kinetics of electroless Ni–P–B plating of quartz optical fiber,” Opt. Mater., vol. 31, no. 10, pp. 1532–1539, 2009.

[10]     R. Taheri, “Evaluation of Electroless Nickel-Phosphorus ( EN ) Coatings,” PhD Thesis, no. August 2002, 2003.

[11]     R. K. Upadhyay and L. A. Kumaraswamidhas, “Surface modification by multilayered W/W2N coating,” Surf. Eng., vol. 30, pp. 475–482, 2014.

[12]     F. Gao, Q. Yang, R. Liu, and X. Huang, “Oxidation resistance of novel multilayer coatings for gas turbine components,” Surf. Eng., vol. 30, no. 9, pp. 624–635, 2014.

[13]     N. E. Beliardouh, K. Bouzid, C. Nouveau, B. Tlili, and M. J. Walock, “Tribological and electrochemical performances of Cr/CrN and Cr/CrN/CrAlN multilayer coatings deposited by RF magnetron sputtering,” Trib. Inter., vol. 82, pp. 443–452, 2015.

[14]     M. A. Al-Bukhaiti, K. A. Al-hatab, W. Tillmann, F. Hoffmann, and T. Sprute, “Tribological and mechanical properties of Ti/TiAlN/TiAlCN nanoscale multilayer PVD coatings deposited on AISI H11 hot work tool steel,” Appl. Surf. Sci., vol. 318, pp. 180–190, 2014.

[15]     Ö. Baran, F. Bidev, H. Çiçek, L. Kara, İ. Efeoğlu, and T. Küçükömeroğlu, “Investigation of the friction and wear properties of Ti/TiB2/MoS2 graded-composite coatings deposited by CFUBMS under air and vacuum conditions,” Surf. Coat. Technol., vol. 260, pp. 310–315, 2014.

[16]     S. Foppiano, S. J. Marshall, E. Saiz, A. P. Tomsia, and G. W. Marshall, “Functionally graded bioactive coatings: Reproducibility and stability of the coating under cell culture conditions,” Acta Biomater., vol. 2, no. 2, pp. 133–142, 2006.

[17]     T. S. N. S. Narayanan, I. Baskaran, K. Krishnaveni, and S. Parthiban, “Deposition of electroless Ni – P graded coatings and evaluation of their corrosion resistance,” Surf. Coat. Technol. vol. 200, pp. 3438–3445, 2006.

[18]     W. X. Zhang, Z. H. Jiang, G. Y. Li, Q. Jiang, and J. S. Lian, “Electroless Ni-P / Ni-B duplex coatings for improving the hardness and the corrosion resistance of AZ91D magnesium alloy,” Appl. Surf. Sci., vol. 254, pp. 4949–4955, 2008.

[19]     T. S. N. S. Narayanan, K. Krishnaveni, and S. K. Seshadri, “Electroless Ni-P/Ni-B duplex coatings: Preparation and evaluation of microhardness, wear and corrosion resistance,” Mater. Chem. Phys., vol. 82, no. 3, pp. 771–779, 2003.

[20]     G. K. Williamson and W. H. Hall, “X-ray line broadening from filed aluminium and wolfram,” Acta Metall., vol. 1, p. 22, 1953.

[21]     D. T. Gawne and U. Ma, “Engineering properties of chromium plating and electroless and electroplated nickel,” surf. eng., vol. 4, pp. 239–249, 1988.

[22]     A. Leyland and  a. Matthews, “On the significance of the H/E ratio in wear control: A nanocomposite coating approach to optimised tribological behaviour,” Wear, vol. 246, no. 1–2, pp. 1–11, 2000.

[23]     A. Matthews and A. Leyland, “Materials Related Aspects of Nanostructured Tribological Coatings,” in 51st. Annual Technical Conferebce, 2008, pp. 40–45.

[24]     L. Wang, Y. Gao, Q. Xue, H. Liu, and T. Xu, “A novel electrodeposited Ni – P gradient deposit for replacement of conventional hard chromium,” Surf. Coat. Technol., vol. 200, pp. 3719–3726, 2006.