Effects of Surface Pretreatment to the Properties of Aluminum Oxide (Al₂O₃) Cutting Tool Coated Amorphous Graphite

Abstract:

Hydrofluoric Acid (HF) and sand blasting have been incorporated together with chemical surface pretreatment (HF) for the surface pretreatment of the Al₂O₃ cutting tool. Amorphous graphite was deposited on the substrates by using PVD technique. Morphological observation by Scanning Electron Microscope (SEM), surface roughness and topography of the substrate by using Atomic Force Microscopy (AFM) was done in order to investigate the effect of surface pretreatment on the substrates. Critical load required in scratching the substrate’s surface after coating by different surface pretreatment was evaluated by microscratch testing. As-received micrograph has a continuous 45° direction based on horizontal line when the substrate was put in the chamber at the time the image was taken. Substrate with surface pretreatment shows non-uniform surface with peak and valley image. Coated surface micrograph shows amorphous graphite with cube in shape. Surface roughness and critical load for microscratch of sample was found increased with surface pretreatment both chemically and mechanically.

• Periodical: Advanced Materials Research (Volumes 463-464)
• Pages: 369-374
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.463-464.369
• Online since: February 2012
• Authors: J. Ramli, D.N. Awang Sh’ri, Nasrul Azuan Alang, Yusof Nor Imrah, M.M. Mahat
• Keywords: Aluminium Oxide, Coating, Microscratch, Morphological, Roughness, Surface Pretreatment

References

[1] Qiu-ping Wei, Z.M. Yu, Michael N.R. Ashfold, J. Ye, L. Ma., Synthesis of micro- or nano crystalline diamond films on WC-Co substrates with various pretreatments by hot filament chemical vapor deposition, (2010).

DOI: 10.1016/j.apsusc.2010.02.031

[2] D. N Awang Sh'ri and E. Hamzah, Effect of Surface Pretreatments on Nanocrystalline Diamond Deposited On Silicon Nitride Substrates, World Academy of Science, Engineering and Technology, (2010).

[3] Liu, H. and D.S. Dandy, Diamond Chemical Vapor Deposition: Nucleation and early growth stage, Noyes Publications: Park Ridge, N. J, (2010).

[4] Chowdhury, S., E. d. Barra, and M.T. Laugier., Study of mechanical properties of CVD diamond on SiC substrates. Diamond and Related Materials. 13, (2004) : p.1625– 1631.

DOI: 10.1016/j.diamond.2004.01.011

[5] S. Marinkovic, S. Stankovic, Z. Rakocievic. (1999), Effects of cemented carbide surface pretreatment in combustion flame chemical vapour deposition of diamond.

[6] Liang, X., et al., , Effect of pressure on nanocrystalline diamond films deposition by hot filament CVD technique from CH4/H2 gas mixture. Surface and Coatings Technology. 202(2), (2007) : pp.261-267.

DOI: 10.1016/j.surfcoat.2007.05.032

[7] R. Haubner, S. Kubelka, B. Lux, M. Griesser and M. Grasserbauer. Murakami and H2SO4/H202 Pretreatment of WC-Co Hard Metal Substrates to Increase the Adhesion of CVD Diamond Coatings, Journal de Physique 11, Volume 5, (1995).

DOI: 10.1051/jphyscol:1995589

[8] Kubelka S., Haubner R., Lux B., Steiner R., Stingeder G. and Grasserbauer M., Diamond Films and technology (in press).