Optimizing 3D Printed Metallic Object’s Postprocessing: A Case of Gamma-TiAl Alloys

Abstract

Gamma-TiAl (γ-TiAl) alloys can be used in high-end products relevant to the aerospace, defense, biomedical, and marine industries. Fabricating objects made of γ-TiAl alloys needs an additive manufacturing process called Electron Beam Melting (EBM) or other similar processes because these alloys are difficult-to-cut materials. An object fabricated by EBM exhibits poor surface finish and must undergo postprocessing. In this study, cylindrical specimens were fabricated by EBM and post-processed by turning at different cutting conditions (cutting speed, depth of cut, feed rate, insert radius, and coolant flowrate). The EBM conditions were as follows: average powder size 110 μm, acceleration voltage 60 kV, beam current 10 mA, beam scanning speed 2200 mm/s, and beam focus offset 0.20 mm. The surface roughness and cutting force were recorded for each set of cutting conditions. The values of the cutting conditions were set by the L36 Design of Experiment approach. The effects of the cutting conditions on surface roughness and cutting force are elucidated by constructing the possibility distributions (triangular fuzzy numbers) from the experimental data. Finally, the optimal cutting conditions to improve the surface finish of specimens made of γ-TiAl alloys are determined using the possibility distributions. Thus, this study’s outcomes can be used to develop intelligent systems for optimizing additive manufacturing processes.

Effect of Minimum Quantity of Lubricant on Carbide Tools and Surface Integrity in the Machining of Titanium Aluminides

“…Manufacturing processes such as casting [9], powder metallurgy, ingot metallurgy, vacuum arc remelting (VAR), and, thanks to the recent advance of additive manufacturing [10,11], electron beam melting (EBM) [12], are applicable. The major disadvantage of these manufacturing procedures is that the part surface quality and the geometrical precision achieved do not fulfill the challenging specifications of the aeronautical sector [13]. Hence, it is imperative to undergo some finishing machining processes to fulfill the necessary criteria.…”

Evaluation of Machining-Induced Chatter and Part Quality in TiAl Alloys Turning Processes by Means of Harmonics Analysis

“…In recent years, processes such as vacuum arc remelting (VAR), from large electrodes of Ti and Al in an inert atmosphere, or electron beam melting (EBM) have been identified as valid [6], [7]. However, all these manufacturing processes result in a surface quality that is not suitable for the requested applications, and final machining operations are necessary to adapt the surface integrity of the parts to the use requirements [8].…”