A self designed Split Hopkinson tensile bar setup with a rotating disk was used to investigate room temperature tensile properties of a γ TiAl alloy in duplex (DP) and fully lamellar (FL) microstructural forms under the dynamic strain rates between 70 and 800 s -1 . It was found that for both forms the alloy is brittle at these strain rates, exhibiting near zero ductility. The σ b at dynamic strain rate is greater than that at the static strain rate of 5×10 -1 s -1 , and the σ b of the DP material is higher than that of the FL material. Fractography analysis indicated that both materials at dynamic strain rates fracture in a mixed mode of predominant transgranular cleavage and minor intergranular cracking, which is similar to that at the static strain rate. The room temperature brittleness of the alloy is not environmentally related. : A self designed Split Hopkinson tensile bar setup with a rotating disk was used to investigate room temperature tensile properties of a γ TiAl alloy in duplex (DP) and fully lamellar (FL) microstructural forms under the dynamic strain rates between 70 and 800 s -1 . It was found that for both forms the alloy is brittle at these strain rates, exhibiting near zero ductility. The σ b at dynamic strain rate is greater than that at the static strain rate of 5×10 -1 s -1 , and the σ b of the DP material is higher than that of the FL material. Fractography analysis indicated that both materials at dynamic strain rates fracture in a mixed mode of predominant transgranular cleavage and minor intergranular cracking, which is similar to that at the static strain rate. The room temperature brittleness of the alloy is not environmentally related.
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