Effect of ceramic particle reinforcement type and process parameters on abrasive water jet processing of aluminum metal matrix composites fabricated by stir casting and hot rolling

Abstract

In the present study, three AA6061 composites reinforced with 8% SiC, B₄C, and Al₂O₃ were produced using the stir casting method. The composite specimens were molded in the thickness of 20 mm, and then the thicknesses of the samples were reduced to 7 mm by employing a hot rolling process at 450 °C. The effect of abrasive water jet cutting parameters such as nozzle speed (NS) and stand-off distance (SOD) on the kerf taper angle (KTA) and surface roughness (SR) were studied. The experiments were conducted based on the Taguchi L9 orthogonal array and the experimental results were analyzed by using the analysis of variance (ANOVA). The test results revealed that the most effective cutting variable on the KTA and SR was the type of reinforcement ceramic particle. The lowest KTA and the best SR values were recorded in the cutting of the Al₂O₃-reinforced composite specimen. The influence of the ceramic particle reinforcements on the SR and KTA was 60.6% and 65.1%, respectively. The effect ratio of the SOD, the second most effective process variable, to the SR is 28.1%, while the effect ratio to the KTA is 22.0%. Predictive models were developed for the KTA (R² = 93.29%) and SR (R² = 91.84) by the regression analysis. A close correlation with the ratio of 95.43% was achieved between the KTA and SR.