**Investigating the Ability of Process Parameters to Reduce Defects during the Drilling of Carbon-Fiber-Reinforced Plastic (CFRP) and Aluminum Stack †**

**Muhammad Waseem \*, Salman Hussain, Muhammad Waqas Hanif and Muhammad Jawad**

Department of Industrial Engineering, University of Engineering and Technology Taxila, Punjab 47050, Pakistan; salman.hussain@uettaxila.edu.pk (S.H.); waqas.hanif@students.uettaxila.edu.pk (M.W.H.); engr.jawad@uettaxila.edu.pk (M.J.)

**\*** Correspondence: waseemime@gmail.com

† Presented at the Third International Conference on Advances in Mechanical Engineering 2023 (ICAME-23), Islamabad, Pakistan, 24 August 2023.

**Abstract:** The effects of drilling process parameters, such as drill diameter and feed rate, on the delamination of holes has been examined while drilling Carbon-Fiber-Reinforced Plastics and aluminum (CFRP/Al2219-T6). The stack method was employed while drilling in order to reduce the defects in the drilling process and enhance the quality of the holes produced. A total of nine experiments were performed using the central composite design. An analysis of variance (ANOVA) revealed that feed rate and drill size have significant effects on the delamination of holes. The experimental results show that the minimum delamination value (1.018) was obtained at a feed rate of 26.5 mm/min and with a drill diameter of 6.5 mm.

**Keywords:** CFRP/Al2219-T6 stack; delamination; drill diameter; feed rate
