Erosive wear and topographical study of zinc-aluminum based composite reinforced with in-situ formed ZrB2 particles

The present study deals with the erosive wear behaviour of a zinc-aluminum (ZA) alloy and composite in the slurry medium. The effects of reinforcement of zirconium diboride (ZrB2) particles in ZA alloy, as well as the impingement angle and duration of erosion wear responses have been studied. The slurry composition was prepared with 1.5 L of water and 500 g silica of a size range of 350-450 mu m. The erosion tests are performed at a speed of 600 rpm for varying durations (20-80 h) and impingement angles (30 degrees-90 degrees). The erosive wear responses of the samples have been analyzed in terms of distinct features of their micro constituents like ZrB2 and the material removal mechanism in a prescribed set of conditions. A significant decrease in composite erosion compared to ZA alloy has been observed. With increased duration, both alloy and composite show increased erosive wear. Obtained results revealed that the composite shows 60-80 % less erosive wear than ZA alloy on operating conditions. The optimum results in wear have been observed at 45 degrees for alloy and 60 degrees for composite. Investigating topographical aspects using scanning electron microscopy and atomic force microscopy revealed that ZrB2 reinforcements resulted in smoother topography and reduced erosive wear.