Machinability Study of AA6061 Under Various Heat Treatment Conditions

Referring to extensive use of aluminum alloy (AA) 6061 in various types of industrial divisions, adequate knowledge of factors governing machinability aspects of AA 6061 under different heat treatment conditions (T6, T4, and T651) is important. This subject has received limited attention in the literature. Therefore, surface roughness, cutting force, tool wear as well as burr formation morphology, and chip shape were considered as the main machinability attributes during dry drilling tests. Under specific conditions, the bio-lubricant was used, and the obtained results were compared with those recorded under dry condition. Although heat treatment conditions may increase the hardness of the work parts, consequently higher cutting force and more built up edge were observed under dry condition. Although better machinability was observed under lubricated tests, however, due to interaction effects between cutting parameters, an adequate selection of cutting tool material and geometry as well as lubrication strategy and flow rate are of prime choice in order to improve the machinability of heat treated work parts.