Investigation of Temperature Variation During Friction Drilling of 6082 and 7075 Al-Alloys

Friction drilling is used to process special holes with a bushing and a boss in thin sheet metals without producing chips via a non-traditional tool-drill. Friction drilling parameters involve the feed rate, rotational speed and profile dimensions of the drilling tool, which directly affect the induced bushings dimensions, as well as, the microstructure of the produced hole. In the present study, friction drilling parameters were manipulated during the performance of friction drilling of 6082 and 7075 Al-alloys, moreover, the temperature variation in the tool-work-piece interface was recorded during the drilling processes via an infrared camera and four thermocouples located at different positions near the drilling zone. During the formation of the bushing and the boss in the investigated aluminum sheet metals, the minimum measured temperature was 220 °C and the maximum measured temperature was 380 °C. It was found that the temperature in the tool-work-piece interface increased with the reduction of the feed rates and the increase of both of the rotating speeds and the tool cone angles. Furthermore, the surface roughness values of the drilled holes were found to be increased with the increase of the rotational speeds.