Effects of surface condition on fatigue properties of a medium-strength γ-TiAl alloy Ti-45Al-5Nb-lW(at%) were investigated.It is found that the maximum stresses of fatigue samples are lower than the yield stresses of the medium-strength γ-TiAl alloy.Meanwhile,the local plastic deformation is unconspicuous to occur at the crack tip.In this case,the fatigue strength is mainly decided by surface conditions of maximum-stressed surface,but compressive stress and deformation especially resulted from shot peening play an important role in the improvement of the condition fatigue strength.The affecting depth of shot peening is about 250 μm.As a result,the relatively weak microstructures and phases become the preferential initiation sites and propagation routes.They are observed to be equiaxed γ grains,B2 + ω grains,and α_2-γ lamellar interface in soft orientations.The existence of V-notch can significantly reduce the fatigue properties of the samples.
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机译:平成28年度论文赏受赏轮文:Effect of Si/Fe Composition, Substrate Temperature, and Substrate Orientation on the Structure and Magnetic Properties of Fe-Si Alloy Film
机译:利用扫描穿隧显微镜探讨在硒化铟上未氧化表面和氧化表面之介面接合处的电子特性 =Scanning Tunneling Microscope study of InSe Surface Electronic Properties at the Fresh/Oxided Interface Junction