About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
|
Advances in Titanium Technology
|
Presentation Title |
Adiabatic Heating and Phase Transformation in Serrated Chips of Ti-6Al-4V during Turning |
Author(s) |
Jiawei Lu, Thomas R. Bieler, Ryan Khawarizmi, Patrick Kwon |
On-Site Speaker (Planned) |
Thomas R. Bieler |
Abstract Scope |
The wear rate on tools when machining titanium alloys increases dramatically with increasing cutting rate. This may result from transformation from alpha to beta phase at the chip-tool interface where beta more aggressively attacks the tool. Chips from turning experiments at 1, 1.5, and 2 m/s (61, 90, 122 m/min) were examined using EBSD mapping to identify mechanisms causing serrated chips, along with 2-D simulations using a Johnson-Cook model in DEFORM to assess local strain and temperature history in the tool and chip. Temperatures exceed 800 C where the fastest tool wear occurs. The stress tensor where shear instabilities commence was used to assess likely slip system activation in chips with and without cracks; those with cracks had orientations that favored <c+a> slip. Chips were heat treated to use recovery and recrystallization to infer the internal state of shear bands, and evidence for transformation to the beta phase is assessed. |
Proceedings Inclusion? |
Planned: |
Keywords |
Titanium, Shaping and Forming, Modeling and Simulation |