Whisker alignment of Ti±6Al±4V/TiB composites during deformation by transformation superplasticity
نویسندگان
چکیده
We examine the eect of 10 vol.% TiB whisker reinforcement on transformation superplasticity of Ti±6Al±4V, induced by thermal cycling about the a/b phase transformation range of the matrix under a uniaxial tensile stress. During superplastic deformation, the whiskers gradually align along the external loading axis, as measured by electron back-scattering diffraction of deformed specimens. The composites exhibit a gradual decrease in eective deformation rate during superplastic elongation. This eect is attributed to increased load transfer from matrix to whisker upon whisker alignment, and is explained with elastic calculations of stress partitioning. # 2001 Elsevier Science Ltd. All rights reserved.
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