Limin DONG
,
Rui YANG
材料科学技术（英文）
The influences of alloying elements W, Mo, Cr, and Nb on retained β phase in 47Al based near γ-TiAl alloys have been studied. The results reveal that the amount of retained β phase is increased by the addition of Cr, Mo, W in rising rank, although the distribution of β phase in Cr-bearing alloys is different from that of Mo- or W-bearing alloys. For Nb-doped alloys, no retainedβwas found even when 5 at.pct Nb was added. The as-cast microstructural features and the distribution of theβphase in the different alloy families were compared and interpreted in terms of the different segregation behaviour of these elements in Ti.
关键词:
γ-TiAl
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null
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null
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null
Physical Review B
In a recent publication [S. Dong et al., Phys. Rev. Lett. 103, 127201 (2009)], two (related) mechanisms were proposed to understand the intrinsic exchange bias present in oxides heterostructures involving G-type antiferromagnetic perovskites. The first mechanism is driven by the Dzyaloshinskii-Moriya interaction, which is a spin-orbit coupling effect. The second is induced by the ferroelectric polarization, and it is only active in heterostructures involving multiferroics. Using the SrRuO(3)/SrMnO(3) superlattice as a model system, density-functional calculations are here performed to verify the two proposals. This proof-of-principle calculation provides convincing evidence that qualitatively supports both proposals.
关键词:
thin-films;weak ferromagnetism;superlattices;anisotropy;bifeo3;srruo3;model
