TRANSACTION PAPER

 

Microstructure and corrosion properties of Al(Ni/TiB₂) intermetallic matrix composite coatings

 

 

A.P.I. Popoola^I; S.L. Pityana^II; O.M. Popoola^I

^ITshwane University of Technology, Pretoria, South Africa
^IICenter for Scientific and Industrial Research-National Laser Centre, Pretoria, South Africa

 

 

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SYNOPSIS

Laser coatings are used for a wide variety of applications. TiB₂/Ni intermetallic matrix composite coatings were fabricated on Alsubstrate by a high power Rofin Sinar Nd: YAG solid-state laser. The characterization of the coatings was carried out by optical microscopy (OM), scanning electron microscopy (SEM/EDS) and Xray Diffraction (XRD). Electrochemical study of the laser coatings in 3.65 per cent NaCl at room temperature revealed that with very high weight proportion of nickel the corrosion resistance of the coatings deteriorated due the presence of AlB10 phase. 50 wt per cent TiB₂+50 wt per cent Ni laser coatings exhibited the highest corrosion resistance in test solution.

Keywords: Corrosion, protective film, laser surface alloying, reinforcement

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