| The relationship between microstructure and mechanical properties of the near-βTi-10-V2Fe-3Al alloy has been investigated. Microstructural variations were made by either changing heat treatment or imposing the thermomechanical processing prior to heat treatment. In the β-solution treated(ST) and aged structure, brittle fracture occurred during the tensile tests, presumably due to the precipitations of fine secondary a particles in the metastable β matrix. The presence of primary a in the (α+β)-ST and aged structure represented high ductility, about 10%. The increase in ductility was, however, limited by the formation of thick grain boundary α-film. Thermomechanical processing was found to be effective in increasing yield and tensile strength of the alloy. In order to get a good combination of strength and toughness it is thus, suggested that microstructure should be modified not to contain any grain boundary α, but to contain globular primary αin small β grains. |
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