Parameters Controlling Drilling and Tapping Characteristics of Aluminum Based Alloys

The present study was performed on an Al-6% Cu-0.7%Si alloyAlloys, and 319 and 356 alloysAlloys following different heat treatmentsHeat treatment. The main task was to evaluate the drillingDrilling and tappingTapping characteristics of the Al-Cu alloyAlloys with respect to the Al-Si based 319 and 356 alloysAlloys. The drillingDrilling work was carried out on a Huron K2X8five CNC machine at 15,000 rpm with continuous cooling to absorb the heat and clean the holes from the chips formed during the drillingDrilling operationOperation. The results show that addition of Si coupled with T6 agingAging treatment produces the highest cutting forcesCutting forces (about 360N) among the alloysAlloys studied (approximately 270N) after 2500 holes. Considering the Al-Cu based alloysAlloys, varying the agingAging treatment has practically no significant bearing on the cutting forcesCutting forces. Apparently, a high Cu content acts as a self-lubricant, facilitating the drillingDrilling process up to 2700 holes, with no sign of tool wearTool wear. However, due to the low level of Si in the Al-Cu based alloyAlloys, built-up edge (BUEBUE) is more frequent, with conical chips, which would affect the precision of the size of the drilled hole. The chips are normally dull and characterized by their rough surfacesSurface compared to those obtained from A356A356.0 alloyAlloys.