Fang WANG
金属学报(英文版)
A new model for the analysis of fatigue crack growth in the metal structures was proposed. This model shows a promising capability of explaining various fatigue phenomena. The new crack growth model is further completed by a continuous empirical formula for estimating the value of variable fracture toughness during crack propagation and a modified continuous equation for the crack tip stress/strain constraint factor used to calculate the stress intensity factor at the opening level. The prediction results are proved to agree well with the observed phenomena in test.
关键词:
Marine structures
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Crack growth rate
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Three dimensional stress state
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Fracture toughness
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Crack tip stress/strain constraint factor
Wenfeng LIU
,
Fang WANG
,
Xiaohong XU
金属学报(英文版)
doi:10.1016/S1006-7191(08)60113-1
FePt/Ag thin films were deposited by magnetron sputtering onto 7059 glass substrates, then were annealed at 550 ℃ for 30~min. Nanostructured FePt/Ag films were successfully obtained with the magnetic easy axis of L10 FePt perpendicular to the film plane. It was found that the development of (001) texture depended strongly on the thicknesses of FePt magnetic layer and Ag underlayer. The L10 ordered FePt(15 nm)/Ag(50 nm) with (001) orientation can be obtained. And the perpendicular coercivity of FePt(15 nm)/Ag(50 nm) film reached to 7.21×105 A/m, whereas the longitudinal one was only 3.2×104 A/m. The non-magnetic Ag underlayer can not only induce (001) orientation and ordering of FePt grains, but also reduce the intergrain interactions.
关键词:
FePt/Ag thin films
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null
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null
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null
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