Laser processing of nickel-aluminum bronze for improved surface corrosion properties

Nickel-aluminum bronze was subjected to laser heating to change the microstructure on the surface for enhanced corrosion performance. To develop the laser processing parameters, a two-phase diffusion model was used to determine the phase transformation kinetics. Also, an analytical laser heating model was employed to determine the laser power setting required to process just below the melting point. The result was that the lamellar k(III) phase of the as-cast microstructure was dissolved up to 1.3 mm deep. Electrochemical testing revealed an increase in the corrosion potential and hence improved corrosion resistance for the laser processed surface, supporting the use of this process for enhanced corrosion performance of nickel-aluminum bronze components. (C) 2013 Laser Institute of America.