Enhancement of Machining Quality in Polymeric CNT-Reinforced Composites Subjected to Thermal Fatigue

Thermal fatigue is one of the most important issues in different engineering fields. The importance of this phenomenon is its application in aerospace industries and considerable effects on the material properties. In this research, the effect of thermal fatigue on the machining quality of polymeric CNT-reinforced composites is studied. To follow this aim, initially the composite specimens with eight layers in symmetrical and unsymmetrical layups are fabricated and subjected to thermal cycling. Then, two different machining processes including conventional drilling and ultrasonic vibration assisted drilling are carried out and the thermal fatigue effects are experimentally studied. Additionally, the effects of various parameters including “addition of multi wall carbon nanotube”, “machining process” and “layup method” on machining quality of composites under thermal fatigue condition is investigated in order to obtain the least delamination. The results indicated that addition of multi-walled carbon nanotubes enhances the machining quality up to 13%. It was also revealed that the implement of ultrasonic assisted drilling could reduce the delamination damage up to 10%.