| Dynamic deformation behavior of a 93W-4.9Ni-2.1Fe heavy alloy was investigated using torsional Kolsky bar in order to evaluate its adiabatic shear banding behavior. Dynamic (γ˙∼10³/sec) torsional tests were conducted for four samples fabricated by the different processing conditions, i.e., sintered, heat-treated, swaged, and aged, and then the test data were compared with those of the quasi-static(γ˙10^(-4)/sec) tests. Dynamic test results showed that the maximum shear stress was increased in the order of the sintered, the heat-treated, the swaged, and the aged samples. In the swaged and the aged samples, the shear stress dropped abruptly after it reached to the maximum shear stress point and the shear strain to the maximum shear stress point were considerably small compared to those of the sintered and the heat-treated samples. The phenomena indicated the higher possibility of forming adiabatic shear bands in the swaged and the aged samples than the sintered and the heat-treated samples. The observation of the deformed areas of the fractured torsional specimens indicated that shear deformation was concentrated to the center of the gage section in the case of the swaged and the aged samples, whereas it was homogeneously distributed in the case of the sintered and the heat-treated samples. This deformation behavior correlated well with the shear stress-shear strain curves, suggesting that the torsional Kolsky bar technique is a good tool for evaluating the adiabatic shear banding behavior of the tungsten heavy alloys. |
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