The effect of temperature on slip in microtextured Ti-6Al-2Sn-4Zr-2Mo under dwell fatigue

摘要

Slip activity in dwell fatigued Ti-6Al-2Sn-4Zr-2Mo, and its relation to the microstructure, was investigated using digital image correlation and electron backscatter diffraction at room temperature, 120 °C, and 200 °C to span a range of dwell sensitivities. The grains through which slip traces traversed were examined to identify critical grain characteristics in the percolation of long-range slip. It was found that slip accumulated more rapidly and in greater amounts at temperatures that exhibit dwell sensitivity (room temperature and 120 °C) versus temperatures that do not (200 °C). At all temperatures, plasticity occurred primarily by long-range basal slip through co-located grains with a high basal Schmid factor.