Modeling Of Drilling Operatıon For Superalloys With Finite Element Method

Thesis Type: Postgraduate

Institution Of The Thesis: Gazi University, Fen Bilimleri Enstitüsü, Turkey

Approval Date: 2020

Thesis Language: English


Supervisor: Yavuz Zümrüt


Finite element method has been used widely in metal cutting simulations in the last years. This method provides selecting the most advantageous cutting parameters for complex metal cutting operations, in terms of cost and time. In this thesis, drilling operation of aged Incoloy A286 superalloy, annealed and aged Inconel 718 superalloys were modeled numerically using Deform-3D V.11; and the effects of feed rate and cutting speed on thrust force and cutting torque were investigated. Two different feed rates and cutting speeds were used for drilling simulations for each material. In the drilling simulations of Incoloy A286, two twist drills with diameter 8.38 mm, helix angle 28 degree, point angles 120 degree and 140 degree found in the industry were scanned with 3D cameras and modelled again, then imported to the Deform-3D program. The twist drill used in the drilling simulations of Inconel 718 has a diameter of 5 mm, helix angle of 30 degrees and point angle of 140 degrees, which was modelled in the Deform-3D program. In the drilling simulations, Johnson-Cook material model was applied. Flow stress parameters of Incoloy A286, which were not avaliable in the literature, were determined using quasi-static tensile tests at room temperature and Split-Hopkinson dynamic compression tests at room and high temperatures, while the parameters for Inconel 718 were obtained from the literature. The numerical results were agreed with the studies in the literature. The thrust force and torque were increased with the increase of feed rate and decreased with the increase of cutting speed within the studied cutting speed range.