Monday  |  Executive CD  |  11:20 AM–11:40 AM

#19402, Rate Effects on the Thermo-Mechanical Compressive Response of the Metastable Beta Ti Alloy, Ti-15Mo (wt.%)

Titanium (Ti) and its alloys are widely used in defense, aerospace, and automotive industries due to their excellent strength-to-weight ratio and corrosion resistance. These components often face dynamic events with elevated temperatures. Alloys exhibiting Twinning Induced Plasticity (TWIP) are of particular interest for dynamic applications due to enhanced toughness and ductility. Despite their promise, there is limited understanding of the dynamic mechanical behavior of TWIP Ti alloys at elevated temperatures. This study examines the effects of loading rate and temperature on the compressive behavior and microstructural evolution of the metastable beta phase TWIP Ti-15Mo alloy. Quasi-static (10⁻³ s⁻¹) and dynamic (up to 10³ s⁻¹) compression experiments were conducted using a standard load frame and a uniquely modified Kolsky bar system, both with integrated furnaces. Techniques including 2D digital image correlation (DIC), thermal imaging, and electron backscatter diffraction (EBSD) were used for analysis. Results reveal that higher strain rates promote twinning and reduce work hardening due to adiabatic heating, while smaller grains slightly reduce work hardening at low rates but increase it dynamically. At elevated temperatures, twinning decreases and shifts towards dislocation slip and omega phase precipitation, particularly under quasi-static conditions. These findings enhance our understanding of the strain rate and temperature effects on the deformation mechanisms in Ti-15Mo, informing its potential use in high-performance applications.

Emily Pittman   Colorado School of Mines/Los Alamos National Laboratory
Amy Clarke   Colorado School of Mines/Los Alamos National Laboratory
Leslie Lamberson   Colorado School of Mines