Optimization of Cutting Process Parameters in Inclined Drilling of Inconel 718 Using Finite Element Method and Taguchi Analysis

Abstract

Nickel-based superalloys are famous in the demanding applications. Inconel 718 is one of the most commonly used nickel-based superalloys due to its extraordinary inherent properties. Inconel 718 is a suitable material for high temperature applications due to the properties such as anti-oxidization, high hot hardness, high creep, and fatigue strength. Drilling operation is one of the most widely used manufacturing operations in almost all industrial sectors. However, drilling operation is very complex in nature due to the presence of intricate geometry of the drill bit. In conventional drilling, cutting is performed by the combined action of the chisel edge and the two or more cutting lips. In depth analysis of the cutting process shows that chisel edge starts with an indentation at the center of the twist drill. Then away from the center, chisel edge performs orthogonal cutting with negative rake angle. Whereas, cutting action at the cutting lip is oblique in nature, and force analysis involves the use of element formulation due to involvement of radius. It is rarely found in the literature where drilling operation at different inclination angles is conducted and analyzed. The presented study numerically investigates the cutting performance of drilling operation, when operated at different inclination angles. The study revealed cutting force variation at different inclination angles due to the different tool workpiece engagement for each inclination. The magnitude of thrust force increased when inclination angle is changed from 30° to 60°. It can be linked with the higher chip load initially in this case as compared to the 30° inclination angle. The cutting temperature was affected by spindle speed (53.7%), followed by feed rate (33.31%) and inclination angle (3.44%).

Precision Hard Turning of Ti6Al4V Using Polycrystalline Diamond Inserts: Surface Quality, Cutting Temperature and Productivity in Conventional and High-Speed Machining

“…The low thermal conductivity of titanium alloys prevents the dissipation of heat generated during cutting, resulting in the very high temperature of the cutting zone which causes damage to the machined surface and cutting tool [ 30 ]. Cutting temperature generated during machining is significantly influenced by cutting conditions [ 31 , 32 ] and cutting tool materials and geometry [ 33 , 34 ]. Various studies have been conducted in order to reduce the temperature during the machining of titanium alloys, and these have been based on optimizing cutting conditions or used methods such as vibration assisted machining [ 35 ] which showed a good result in reducing temperature of cutting, using a rotary tool [ 36 ], using lubrication to reduce friction between the tool and target material [ 37 ] or using emerging cooling systems [ 38 ].…”

Determination of Optimum Test Parameter Level Ranges for Machining Processes

“…The system's reliability did not decrease due to the reduction in the number of experiments. A second benefit of experimental design methods is that the optimum points of (maximum, minimum, nominal) machining parameters, such as surface roughness and cutting forces can be determined [4][5][6][7]. Owing to the benefits stated above, using experimental design methods in manufacturing-oriented experimental studies is essential.…”

Cutting Forces during Inconel 718 Orthogonal Turn-Milling

“…Nickel-based superalloys are used in the aviation and marine industries, as parts of gas turbines, parts of space shuttles and nuclear reactors. These are characterized by high strength at elevated temperatures, high abrasive wear resistance and corrosion resistance, as well as significantly higher creep resistance compared to other materials [ 1 ]. Inconel alloys belong to the group of the difficult-to-machine materials.…”