Effect of NaBH4 concentration on hardness and microstructural properties of electroless deposited St-37 steel

Öz

In this study, electroless Ni-B depositions were achieved on the St-37 steel substrates at different NaBH4 concentrations and 950 oC and 1 hour. Electroless Ni-B deposited samples had a cauliflower-like surface texture that makes the electroless Ni-B deposited surface lubricating naturally and as the NaBH4 concentration increased, the grain size decreases in the microstructure. XRD spectra of the sample showed partial amorph region together with the crystalline region. Microhardness testing of the deposited samples were performed with a microhardness tester under a load of 25 g and an indentation time of 10 s. The highest hardness value was obtained in the sample prepared with 1.4 g/l NaBH4 concentration.

Anahtar Kelimeler

• Deposition
• Microhardness
• Ni-B
• Microstructure
• St-37
• Surface

Proje Numarası

2017-31-07-25-001

Kaynakça

1. Madah, F., Amadeh, A. A., Dehghanian, C., Investigation on the phase transformation of electroless Ni-B coating after dry sliding against alumina ball. Journal of Alloys and Compounds 658., 272-279, 2015.
2. Vitry, V., Delaunois, F., Formation of borohydride- reduced nickel-boron coatings on various steel substrates. Applied Surface Science 359., 692-703, 2015.
3. Krishnavenia, K. Narayanan, T. S. N. S. Seshadrib, S.K., Electroless Ni-B coatings: preparation and evaluation of hardness and wear resistance. Surface & Coatings Technology 190., 115-121, 2005.
4. Zhu, Xiaojing., Processability of Nickel-Boron Nanolayer Coated Boron Carbide. The faculty of the Virginia Polytechnic Institute and State University, Doctoral Thesis, 2008.
5. Vitry, V., Bonin, L., Increase of boron content in electroless nickel-boron coating by modification of plating condition. Surface & Coatings Technology 311., 164-171, 2017.
6. Narayanan, T. S. N. S., Seshadri, S. K., Formation of characterization of borohydride reduced electroless nickel deposites. Journal of Alloys and Compounds 365., 197-205, 2004.
7. Vitry, V., Kanta, A. F., Delaunois, F., Mechanical and wear characterization of electroless nickel-boron coatings. Surface & Coatings Technology 206., 1879-1885, 2011.
8. Riedel, W., “Electroless Nickel Plating”, ASM International Metals Park, Ohio, USA, 1991.

9. Delaunois, F., Petitjean, J.P., Lienard, P., Jacob- Duliere, M., ‘‘Autocatalytic electroless nickel-boron plating on light alloys, Surface and Coatings Technology”, vol. 124, 2000, 201-209.
10. Narayanan, T. S. N. S., Krishnaveni, K., Seshadri, S. K., Electroless Ni-P/Ni-B duplex coatings: preparation and evaluation of microhardness, wear and corrosion resistance, Mater. Chem. Phys. 82 (2003) 771-779.
11. Baudrand, D. W., Electroless Nickel Plating in ASM Handbook, Volume 5: Surface Engineering, 2002.
12. Vitry, V., Electroless Nickel-Boron Deposits: Synthesis, Formation and Characterization; Effect of Heat Treatments; Analytical Modeling of the Structural State, University of Mons, Belgium, 2010.