High-strain-rate response of hot-explosively consolidated W-Ti alloys

Disk-shaped, two-phase, full-density W-Ti alloy billets have been fabricated by a new, hot-explosive-compaction technique. As part of a characterization effort, the compressive behavior of the alloy was investigated. Quasistatic and split Hopkinson pressure bar (SHPB) tests of cylindrical samples, taken from a 83W-17Ti at.% alloy billet, demonstrate the propensity of this material to fail via shear localization at high strain rates. The effects of strain rate, orientation of the matrix phase with respect to the direction of the SHPB compression, and spatial location within the billet (i.e., periphery or core) were evaluated. At quasistatic strain rates, the alloy deformed in a ductile mode and exhibited a definite spatial location sensitivity. At high strain rates, spatial location sensitivity was absent. Shear localization was unaffected by density variations, matrix orientation in the alloy, or the presence of coarsened substructural features in the matrix. These experiments and the microstructural characteristics of the resultant localized regions are discussed.