Multi-Physics Analysis of Machining Ti-6Al-4V Alloy: Experimental Characterization and a New Material Behavior Modeling

Abstract

Titanium alloys are considered difficult-to-cut materials due to their low machinability. Understanding the physical mechanisms occurring during cutting titanium alloys is of particular interest to improve their machinability. Experimental and numerical investigations on Ti-6Al-4V alloy machining are proposed in this paper. Orthogonal cutting tests are performed. The chip microstructure is characterized using SEM observations coupled with the EBSD technique to reveal the deformation mechanisms occurring inside the microstructure. Based on these microscale observations, a new hybrid flow stress model considering the link between the microstructure and damage evolutions is proposed. The model was implemented FE code to simulate the cutting process. The morphology of generated chips and microstructural parameters were deeply analyzed and compared with experimental data. The effect of the dynamic recrystallization phenomenon and its interaction with damage on the cutting process was discussed. The model can be applied for machining simulations of Ti-6Al-4V and other titanium alloys to better choose adequate cutting conditions.

Keywords

• machining Ti-6Al-4V
• cutting process
• physical-based behavior
• microstructure vs. damage
• FE modeling