Determining the Effects of Machining Parameters and Modifier on Surface Roughness in Dry Turning of Al-20%Mg2Si-PMMC using Design of Experiments (DOE)

The machinability of particulate metal matrix composites (PMMC) is influenced by the matrix mechanical properties as well as size, distribution and volume fracture of reinforcement particles. In order to machine different PMMCs, especial machining conditions based on the type of operation must be considered. The main principle aim of this observation is to assess the effect of machining parameters involving cutting speed, feed rate and Strontium addition on surface roughness of Al-20%Mg2Si in-situ composite. In this study design of experiment (DOE) methodology was applied to design experimental trials and the results were analyzed using Analysis of Variance (ANOVA). The dry turning was done on ALPHA 1350S CNC lath machine with a new insert for each test to ensure accurate reporting. The results showed that the Mg2Si particles morphology such as size, shape and distributions have altered by Sr addition. The statistical analysis revealed that all main effects influenced the surface roughness. The predicted results are found to be so closer to actual results. Due to low proximity difference between predicted results and actual results with each other, based on confirmation tests, the predictive model is sufficient accurate at reliability of 95%.