Effect of machining parameters on cutting force and surface roughness of in situ Al-4.5%Cu/TiC metal matrix composites

The present research investigates the feasibility and dry turning characteristics of in situ Al-4.5%Cu/TiC metal matrix composites using uncoated ceramic inserts. The effect of machining parameters such as cutting speed, feed rate and depth of cut on the cutting force and surface roughness of the composites were investigated during the dry turning operations. Experimental results indicated that cutting force increased with cutting speed upto 80 m/min then decreasing upto 120 m/min. Built-up edge (BUE) and chips formation were also examined by scanning electron microscopes. The significant formation of BUE was observed in lower amount at higher cutting speed and higher at lower cutting speed. The length of chip and the number of chip curls increases with an increase in cutting speed at given feed rate and depth of cut. At the same machining condition, C-type chips changes to segmental type chip was influenced by the effect of weight percentage of reinforcement. The investigation revealed that, with the use of uncoated ceramic inserts, acceptable surface finish can be achieved during dry turning operation of the in situ composites.