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In this paper, three kinds of tungsten (W) , respectively, as 0,1,1.4 ( atomic percent ) , with a fully lamellar morphology -cast TiAl alloy (Alloy 0W, Alloy 1W, Alloy 1.4W) at 700 ℃, atmospheric atmosphere , different stress conditions 1000 hours long creep. Creep around in the three alloys microstructure changes carried out a detailed microscopic analysis . Study found that with W content were 0at.%, 1 at.%, 1.4 at.% Slice of the three full- cast TiAl alloys containing creep best 1 at.% W alloy , while containing 1.4 at.% W alloy creep worst. Grain size on Fully Lamellar TiAl alloy creep resistance have a decisive impact . Refined grain size will be significantly reduced the creep performance. W can stabilize stabilize γ and a 2 film layer. After creep at 1000 hours , containing tungsten (W) elements both alloys , the γ and a 2 layers to maintain a stable , non- W alloy its a 2 lamellae appeared parallel decomposition , a 2 sheet content decreased. Also found that a certain amount of B2 ω phase in the grain boundary segregation of Fully Lamellar TiAl alloy on the creep properties is beneficial. Three alloys intragranular dislocation creep mechanisms are slip and climb . In creep , the alloy γ lamellae appeared a large number of dislocations within the γ lamellae after generation will center movement, and wrapped around each plot , while dislocations can not cross a 2 sheet movement.
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