An Experimental and Finite Element Approach for a Better Understanding of Ti-6Al-4V Behavior When Machining under Cryogenic Environment

Abstract

Due to increasing demand in manufacturing industries, process optimization has become a major area of focus for researchers. This research optimizes the cryogenic machining of aerospace titanium alloy Ti-6Al-4V for industrial applications by studying the effect of varying the nozzle position using two parameters: the nozzle’s separation distance from the tool–chip interface and its inclination angle with respect to the tool rake face. A finite element model (FEM) and computational fluid dynamics (CFD) model are used to simulate the cryogenic impingement of cryogenic carbon dioxide on the tool–workpiece geometry. Experiments are conducted to evaluate cutting forces, tool wear, and surface roughness of the workpiece, and the results are related to the CFD and FEM analyses. The nozzle location is shown to have a significant impact on the cutting temperatures and forces, reducing them by up to 45% and 46%, respectively, while the dominant parameter affecting the results is shown to be the separation distance. Cryogenic machining is shown to decrease adhesion-diffusion wear as well as macroscopic brittle chipping of the cutting insert compared to dry turning, while the workpiece surface roughness is found to decrease by 44% in the case of cryogenic machining.

Aero-Engine Blade Cryogenic Cooling Milling Deformation Simulation and Process Parameter Optimization

“…To ensure adequate cooling of the tool, turbulent jets are generally used, and axisymmetric free jets. a is the expansion angle, the jet diffusion angle α is seen in Equation (1). A low-temperature coolant with a pressure of 0.08 MPa and a flow rate of 4 L/min cools the tool intending to reduce the temperature of the cutting area.…”

“…At present, low-temperature machining studies focus on the cutting mechanism, temperature, force, tool wear, and surface integrity. For example, Bejjani R et al [1] investigated the effect of changing the nozzle position on the deep cooling process using the finite element method, CFD method, and experimental methods. Shokrani A et al [2] investigated the most suitable tool geometry for low-temperature machining, which significantly affected the finishing performance of Ti-6Al-4V, increasing the material removal rate; Hong S Y et al [3] directed LN 2 through microjets at the flanks, front edge, or sides near the cutting edge to study its effects.…”

Analysis of Turning Process of Pure Titanium Using Finite Element Method

“…For this reason, many researchers treat in their papers aspects regarding for this estimations, using adequate programs that involve finite element method, [4][5][6][7], for titanium, titanium alloys, carbide alloys or other different materials.…”

Tribo-Device to Quantify of Friction in Rake Face Using Line Contact Mechanism Under Different Machining Conditions. (c2021)

“…These values for the nozzle's position were chosen based on a study done by Bejjani et al [46] where this position led to an optimal cooling effect with minimum cutting forces and tool wear.…”

“…As mentioned before, the cryogenic nozzle is a converging nozzle, placed at a distance of 2cm and inclined at an angle of 15° from the horizontal. These values for the nozzle's position were chosen based on an optimization of the nozzle position for liquid carbon dioxide impingement, done by Bejjani et al [46]. This nozzle position led to an optimal cooling effect and minimum cutting forces and tool wear during machining of AISI 1045 Steel, which is why it is of great interest to assess the effect of this cryogenic fluid on the tribological environment near the cutting zone.…”