Abstract
A modified split Hopkinson bar apparatus is employed to perform orthogonal machining of 6061-T6 aluminum alloy, and an array of HgCdTe high-speed infrared detectors is used to experimentally measure the temperature field distribution at the surface of the workpiece during this process. The effect of rake angle on the temperature field is examined. Three different rake angles are employed, 5,10 and 15 degrees, with two cutting velocities of 30 m/s and 45 m/s at a constant depth of cut of 0.5 mm. It is seen that the rake angle can vary both the maximum temperature as well as the distribution of the temperature field in the chip. For a cutting speed of 30 m/s, the maximum temperature decreased with an increase in rake angle from 251℃ for 5°rake angle to 237℃ for 10°rake angle and 196℃ for 15°rake angle. As the rake angle increases, the primary shear zone in the workpiece contributes less to the temperature distribution and the friction at the tool/chip interface dominates. It is also seen that as the cutting speed increases, maximum temperatures increase and a larger area of the workpiece is affected by the heat generation. For a 5°rake angle, the maximum temperatures increased from 251℃ at 30m/s to 290℃ for 45 m/s cutting speed.
